ACS Publications. Most Trusted. Most Cited. Most Read
Analysis of Nerve Agent Metabolites from Hair for Long-Term Verification of Nerve Agent Exposure
More

OR SEARCH CITATIONS

My Activity
Publications

Figure 1Loading Img
Download Hi-Res ImageDownload to MS-PowerPointCite This:Anal. Chem. 2016, 88, 12, 6523-6530
  • Open Access
  • Editors Choice
Article

Analysis of Nerve Agent Metabolites from Hair for Long-Term Verification of Nerve Agent Exposure
Click to copy article linkArticle link copied!

View Author Information
† Department of Chemistry and Biochemistry, South Dakota State University, Avera Health and Science, Box 2202, Brookings, South Dakota 57007, United States
‡ Pharmacology Branch, Research Division U.S. Army Medical Research Institute of Chemical Defense 3100 Ricketts Point Road, Aberdeen Proving Ground, Maryland 21010, United States
*E-mail: [email protected]. Phone: (605) 688-6698. Fax: (605) 688-6364.
Open PDF

Analytical Chemistry

Cite this: Anal. Chem. 2016, 88, 12, 6523–6530
Click to copy citationCitation copied!
https://doi.org/10.1021/acs.analchem.6b01274
Published May 9, 2016

Copyright © 2016 American Chemical Society. This publication is licensed under these Terms of Use.

Request reuse permissions

Abstract

Click to copy section linkSection link copied!
High Resolution Image
Download MS PowerPoint Slide

Several methods for the bioanalysis of nerve agents or their metabolites have been developed for the verification of nerve agent exposure. However, parent nerve agents and known metabolites are generally rapidly excreted from biological matrixes typically used for analysis (i.e., blood, urine, and tissues), limiting the amount of time after an exposure that verification is feasible. In this study, hair was evaluated as a long-term repository of nerve agent hydrolysis products. Pinacolyl methylphosphonic acid (PMPA; hydrolysis product of soman) and isopropyl methylphosphonic acid (IMPA; hydrolysis product of sarin) were extracted from hair samples with N,N-dimethylformamide and subsequently analyzed by liquid chromatography–tandem mass spectrometry. Limits of detection for PMPA and IMPA were 0.15 μg/kg and 7.5 μg/kg and linear ranges were 0.3–150 μg/kg and 7.5–750 μg/kg, respectively. To evaluate the applicability of the method to verify nerve agent exposure well after the exposure event, rats were exposed to soman, hair was collected after approximately 30 days, and stored for up to 3.5 years prior to initial analysis. PMPA was positively identified in 100% of the soman-exposed rats (N = 8) and was not detected in any of the saline treated animals (N = 6). The hair was reanalyzed 5.5 years after exposure and PMPA was detected in 6 of the 7 (one of the soman-exposed hair samples was completely consumed in the analysis at 3.5 years) rat hair samples (with no PMPA detected in the saline exposed animals). Although analysis of CWA metabolites from hair via this technique is not appropriate as a universal method to determine exposure (i.e., it takes time for the hair to grow above the surface of the skin and typical analysis times are >24 h), it complements existing methods and could become the preferred method for verification of exposure if 10 or more days have elapsed after a suspected exposure.

Copyright © 2016 American Chemical Society

Subjects

what are subjects

Chemical warfare agents (CWAs) were first introduced on the modern battlefield during WWI. Since that point, multiple novel CWAs have been identified, including nerve agents. Nerve agents are of considerable concern due to their extreme toxicity. Sarin, soman, and VX, the most toxic man-made substance known, have dermal LD50 values of 24 mg/kg, 5 mg/kg, and 0.14 mg/kg, respectively. (1, 2)
When exposed to nerve agents, inhibition of acetylcholinesterase (AChE; Figure 1, reaction A) at the serine active site (compound 1) causes the buildup of the neurotransmitter acetylcholine to produce symptoms including copious secretions, loss of consciousness, convulsions, and apnea. While these symptoms may be obvious at high-doses, symptoms of a low-dose exposure (i.e., pupil constriction, rhinorrhea, and mild breathing difficulties) may not be as apparent. (3, 4)

Figure 1

Figure 1. Fate of sarin and soman after binding to serine at the active site of AChE (reaction A). Fluoride reactivation of the AChE enzyme is shown in reaction B. Reaction C depicts aging of the agent–enzyme complex. Reaction D represents cleavage of the agent from the enzyme via hydrolysis. Reaction E describes direct hydrolysis of the parent nerve agent. In the figure, R represents the pinacolyl group of soman or the isopropyl group of sarin.

High Resolution Image
Download MS PowerPoint Slide
Nerve agent exposure can currently be verified by targeting three classes of compounds of interest: (1) alkyl methylphosphonic acids (AMPAs), (5-12) (2) reactivated nerve agents, (13-17) and (3) nerve agent–protein adducts. (18-26) Direct hydrolysis of nerve agents, as shown in Figure 1, reaction E, produces AMPAs (compound 5). AMPAs, however, can also be formed by the release of the nerve agent residue from the serine active site on the enzyme by hydrolysis (Figure 1, reaction D). Reactivated nerve agents are produced when the enzyme-agent complex (compound 3) is reacted with excess KF (reaction B) to reform the original nerve agent and enzyme. The final class of compounds used to verify exposure is nerve agent–protein adducts. The general reaction between proteins and nerve agents is depicted in Figure 1, reaction A, to form agent–protein adducts (compound 3). While the figure depicts reaction with a serine residue, nerve agents have also been shown to react with tyrosine residues on proteins and peptides. (26)
While several methods have been used to detect exposure to nerve agents, (8, 10, 27-29) the main concern with these approaches is that the target parent agents and metabolites have short residence times in the body. The analysis of each of the three classes of compounds used to determine nerve agent exposure listed above has drawbacks. Hydrolysis products are only detectable in most biological matrixes for up to 10 days because of further metabolism and excretion. (7, 8) Reactivated nerve agents are greatly affected by aging (a process in which the alkyl side chain is cleaved from the nerve agent-protein adduct), after which the agent cannot be regenerated. Sarin adducts undergo slow aging (a few hours) while soman adducts age within minutes. (15, 30, 31) However, in either case, the aging process precludes the use of this technique for determination of exposure. The analysis of nerve agent–protein adducts usually requires enzymatic digestion and is thus time and labor intensive. (21) Moreover, while nerve agent–protein adducts may allow for verification while the adducted protein is circulating, the half-lives of the affected proteins are relatively short (e.g., in mammals, the half-life of AChE ranges from 40 h to 2.84 days (32-34) and the half-life of BuChE ranges from 21 h to 5 days (35-38)).
Table 1 lists some methods of retrospective nerve agent analysis methods and their corresponding window of detection (i.e., the maximum amount of time a method or target analyte has been used to verify exposure following an acute toxic agent exposure). With limited windows of detection, the chance for retrospective detection of an exposure is limited if a significant amount of time has passed. In cases where an individual is not exposed to a large enough dose to cause severe symptoms, incorrect diagnosis and treatment could result. Over time, the biomarkers currently used for verification of nerve agent exposure are metabolized and excreted from the body. Therefore, depending on the elapsed time, there may be no method to positively identify a past exposure from typical biological matrixes (i.e., blood, plasma, and urine). This issue can be overcome by discovery of an extremely stable biomarker or a matrix that can preserve known metabolites for long periods of time.
Table 1. Current Windows of Detection of Nerve Agents
classanalytematrixanalysis methodwindow of detection (experimental)ainvestigators
AMPAsIMPAurineGC/MS, GC/MS/MS, GC-FPD2 daysShih et al. (7) Minami et al. (8)
bloodbLC–MS/MS1.5 h, single analysisNoort et al. (10)
bloodbGC/MS14 hShih et al. (7)
 bloodbLC–ESI-MS-TOF180 minEvans et al. (11)
PMPAurineGC/MS2 daysShih et al. (7)
bloodbGC/MS, GC/MS/MS5 min, single analysisFredriksson et al. (9)
reactivated nerve agentreactivated sarinbloodbGC-NP, GC/MS5–10 daysPolhuijs et al. (15)
 tissueGC/MS5–10 daysAdams et al. (16)
reactivated somanbloodbGC/MS5–10 daysAdams et al. (16)
 tissueGC/MS5–10 daysAdams et al. (16)
protein adductsinhibited human butyrylcholinesterasebloodbESI-MS/MS1.5 h, single analysisFidder et al. (21)
 bloodbspectrophotometry (Ellman’s assay)15 min-24 hChe et al. (22)
phosphylated tyrosinedbloodbSPE-LC–MS/MSUp to 24 daysRead et al. (39)
 bloodbLC–IDMS-MS48 hBao et al. (24)
 bloodbimmunoassay15 daysChen et al. (25)
 bloodbLC–MS/MS45 min–7 days, single analysescWilliams et al. (26)
a

Some of the window of detection values correspond to individual samples and not a time course of samples evaluated following an exposure. These types of studies are noted as “single analysis” in the table. In cases where several samples were obtained, the longest amount of time that the analyte was detected is listed. Therefore, the window of detection values listed represent the longest experimentally verified time where an analyte was detected following an exposure, and not necessarily a true window of detection.

b

Blood matrix indicates whole blood, plasma, or serum was used for analysis.

c

Multiple agents, each individually analyzed at different points after exposure.

d

In the case of Chen et al., model compounds were used to simulate nerve agent adducts.

Nerve agent metabolites within the bloodstream are transferred to the hair cells formed in the hair follicle when the follicle is nourished by capillary blood vessels. Once the cells are keratinized, the metabolite is tightly bound at the center of the growing hair shaft, protecting it from further metabolism. (40) After the segment of hair shaft containing the agent or metabolite grows above the skin, the hair can be sampled, extracted, and analyzed to verify a past exposure. Hair analysis was first used for the detection of heavy metals, followed by opiates and other drugs of abuse. (41) The analysis of hair has been extensively studied for popular drugs of abuse, such as cocaine, amphetamines, codeine, morphine, and marijuana. (42-48) Researchers have also used hair samples to identify victims of sexual assault. (42, 49-53) In addition, hair samples have also been used to study exposure to pesticides and other pollutants. (42, 54-60) For example, Tutudaki et al. (61) found that diazinon was present in the hair of rabbits after chronic exposure over a time period of 4 months. Diazinon is an organophosphate pesticide sometimes used as a nerve agent surrogate because of its similar structure, properties, and mechanism of action. The same researchers performed a similar study using rats (45 days), with similar results. (62) Because of its ability to protect metabolites from further metabolism and excretion, hair shows promise as an alternative matrix for retrospective determination, potentially providing a longer window of verification (possibly years) than other methods currently available for nerve agent exposure (Table 1). (42, 48)
Because the symptoms from low-dose nerve agent exposure may be initially dismissed and exposure later suspected, or the exposed individual may not have ready access to medical services, a method able to verify nerve agent exposure at extremely long time periods after a suspected exposure would be very useful. (8, 15, 16, 63, 64) Therefore, the objective of this work was to develop a method for detection of PMPA and IMPA from the hair of soman and sarin exposed individuals as the first technique to use hair to verify exposure to these toxic agents.

Materials and Methods

Click to copy section linkSection link copied!

Materials

All solvents (HPLC grade or higher) and formic acid (≥99%) were obtained from Fisher Scientific (Hanover Park, IL). Pinacolyl methylphosphonic acid, isopropyl methylphosphonic acid, (PMPA, IMPA; each 1000 μg/mL in methanol), D7-IMPA (1000 μg/mL in methanol; 96% isotope purity), and 13C6-PMPA (100 μg/mL in methanol; 95% isotope purity) were obtained from Cerilliant (Round Rock, TX). Aqueous stock solutions (1 μg/mL) were prepared and stored at room temperature. Analytical grade water (18.2 MΩ cm resistivity) was obtained from a Labconco Water Pro PS water purification system.

Hair Samples

Human hair samples used for validation experiments were collected from volunteers under the guidelines approved by the Institutional Review Board of South Dakota State University. Volunteers were allowed to collect and submit their own hair. Gender, race, nationality, health, etc. of the volunteers was not a factor in accepting the hair samples, but any hair that was chemically treated (i.e., permed, dyed, or bleached) was not accepted. If necessary, the hair was cut into short lengths (approximately 1–2 cm) and stored at room temperature until used. If possible, hair from a single volunteer comprised all samples within a single experiment. When more than one volunteer’s sample was used within an experiment, the different hair types were never pooled in an individual sample. To remove any external contamination, the hair was initially washed with a 1% sodium dodecyl sulfate solution. The hair was then rinsed three times with deionized water. Finally, the hair was rinsed with methanol, allowed to air-dry overnight, and was stored at room temperature until used.
Rat hair samples for method application were obtained from the U.S. Army Medical Research Institute of Chemical Defense (USAMRICD) through animal studies conducted in compliance with the Principles of Laboratory Animal Care formulated by the National Society for Medical Research and the Guide for the Care and Use of Laboratory Animals prepared by the National Academy of Sciences and published by the National Institutes of Health. (65) All animal studies were reviewed and approved by the Institutional Animal Care and Use Committee (IACUC). During the study, all animals were single housed and fed a Teklad Rodent Diet No. 8604, with food and water freely available. Bioserve treats were given once per week for enrichment. Six male Sprague–Dawley rats (Charles River Laboratories, Wilmington, MA) weighing approximately 300 g were subcutaneously (sc; lower right flank at hip level) administered saline, while eight rats were exposed (sc) to 1.2 LD50 (132 μg/kg) soman (GD) in the hind leg. No supporting therapy was given after exposure. After 1 week of recovery from the exposure, animals were given isoflurane gas to allow EKG activity monitoring once per week. The animals were euthanized after 28–30 days, and hair samples (2.5–5 g) were collected by shaving the back of each individual animal. Because method development had been initiated with human hair well before the rat hair was received, the entirety of the method validation was completed with human hair.

Sample Preparation

Hair extraction was performed by adding 100 mg of hair into a 2.0 mL centrifuge tube, adding aqueous internal standard (1.5 μg/kg 13C6–PMPA and 150 μg/kg D7-IMPA) and 1.5 mL of N,N-dimethylformamide (DMF), and capping the tube. Spiked and nonspiked (blank) samples were heated for 4 h on a heat block at 70 °C and then shaken for approximately 24 h at room temperature. The DMF was then transferred to a 4 mL glass vial and evaporated at 80 °C to dryness under nitrogen. Dried samples were reconstituted with 0.1% formic acid in a mixture of water and methanol (40:60 water–methanol; 150 μL), syringe-filtered (Millex-GV, 0.22 μm) into a glass insert (150 μL) contained in a screw-top autosampler vial (2 mL), and analyzed by high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS).

Liquid Chromatography–Tandem Mass Spectrometry

HPLC–MS/MS analysis was performed on a Shimadzu LC system (LC-20AD, Shimadzu Corp., Kyoto, Japan) coupled with a Qtrap 5500 triple quadrupole mass spectrometer (AB Sciex, Foster City, CA). Separation was achieved by reversed-phase (RP) chromatography using a Synergi 4 μ Fusion column (50 mm × 2.00 mm; Phenomenex, Torrance, CA). Mobile phase A consisted of 0.1% formic acid in water, mobile phase B was 0.1% formic acid in methanol, and the injection volume was 10 μL. The prepared hair extracts were separated with gradient elution at a flow rate of 0.2 mL/min as follows: the column was initially equilibrated with 60% B, linearly increased to 100% B at 7 min, maintained at 100% B for 1 min, and then decreased linearly back to 60% B over 0.5 min, where the column was equilibrated for the next sample (approximately 2 min). Data acquisition and peak integration were performed with Analyst software, version 1.4.1.
Detection of analytes was achieved by electrospray ionization (ESI)-MS-MS, operating in negative ion mode. Nitrogen (20 psi) was used as the curtain gas. The ion source was operated at −4500 V, a temperature of 500 °C, and a pressure of 14 psi for nebulizer (GS1) and heater (GS2) gases. The entrance potential of the collision cell was −10 V. Multiple reaction monitoring (MRM) was used for analysis of the analytes (Table 2). The declustering potential and collision energy were optimized for each MRM transition and are shown in Table 2. Quantification transitions for IMPA and its internal standard utilized different Q3 masses due to an unstable baseline in the D7-IMPA transition of m/z 144 → 79.
Table 2. Selected MRM Transitions, Optimized Declustering Potentials (DP) and Collision Energies (CE) for Detection of PMPA, IMPA, and Their Internal Standards
compoundQ1Mass (m/z)Q3Mass (m/z)time (ms)DP (V)CE (V)
PMPA (quantification)179.195.040–151.36–22.13
PMPA (identification)179.178.840–73.09–51.75
13C6-PMPA (quantification)185.095.040–89.37–24.51
13C6-PMPA (identification)185.079.040–43.11–39.13
IMPA (quantification)137.079.040–95.97–41.84
IMPA (identification)137.077.040–96.64–35.13
D7-IMPA (quantification)144.395.040–111.66–19.92
D7-IMPA (identification)144.378.940–105.21–46.13

Calibration, Quantification, and Limits of Detection

PMPA and IMPA calibration and quality control (QC) standards were prepared in hair as described in Sample Preparation. Two sets of calibration standards for IMPA (0.75, 1.5, 3, 7.5, 15, 30, 75, 150, 300, and 750 μg/kg) and PMPA (0.15, 0.3, 0.75, 1.5, 3, 7.5, 15, 30, 75, and 150 μg/kg) were used to determine the linear range for both analytes. For the calibration curve, a ratio of analyte peak area to internal standard peak area was plotted versus analyte concentration. Nonweighted and weighted (1/x and 1/x2) fits were examined with a 1/x2 weighted fit producing the best linear description of the calibration data for both PMPA and IMPA as evaluated by the precision and accuracy of the calibration standards. Lower limits of quantification (LLOQ) and upper limits of quantification (ULOQ) were determined via evaluation of calibration standards. Those that had a percent relative standard deviation of <20% (as a measure of precision) as well as an accuracy within ±20% of the nominal concentration back-calculated from the calibration curve, were considered within the linear range. To determine precision and accuracy, three QC concentrations of IMPA (20, 100, and 500 μg/kg) and PMPA (1, 5, and 20 μg/kg) were prepared in hair and analyzed in quintuplicate (N = 5). A new set of high, medium, and low QC standards were analyzed each day for 3 days along with calibration standards (N = 3) for inter- and intra-assay investigations. Precision of the method was considered acceptable if it was <20% and acceptable accuracy was ±20% of the nominal concentration.
Limits of detection (LOD) were determined by analysis of multiple concentrations of PMPA and IMPA. The lowest analyte concentration that consistently produced a signal-to-noise ratio of 3 was defined as the LOD. Noise was determined by observing the baseline noise of the blank hair over the duration of IMPA or PMPA elution.

Selectivity, Recovery, and Stability

Matrix effects were investigated by creating calibration curves for both aqueous and spiked hair (all calibration standards were prepared and analyzed in triplicate) and evaluating the slopes of the resulting curves. Recovery of IMPA and PMPA was determined at low, medium, and high QC concentrations by comparing analyte signals produced from spiked hair and aqueous samples (N = 5). Recovery was calculated as a percentage, relating the peak areas of the spiked hair samples to the peak areas of the aqueous samples.
Short-term autosampler stability was evaluated by placing prepared high IMPA and PMPA QC standards (N = 3) in the LC autosampler. Analysis was performed at approximately 0, 2, 4, 8, 12, and 24 h. Long-term stability of PMPA in hair was evaluated by comparing the results of an initial analysis of the exposed rat hair approximately 3.5 years after collection and a second analysis, approximately 2 years after the first analysis (5.5 years after initial collection).

Results and Discussion

Click to copy section linkSection link copied!

Analysis of PMPA and IMPA by HPLC–MS/MS

The daughter ion mass spectrum produced by negative ESI-MS-MS analysis for the analytes studied, along with m/z assignments for the fragments, is shown in Figure 2. The m/z ratios of 179 and 137 represent PMPA and IMPA, respectively, ([M – H]−). The MRM transition of m/z 179 → 95 was used for quantification of PMPA, and m/z 179 → 79 was used for identification of PMPA. Corresponding transitions of m/z 185 → 95 (quantification) and m/z 185 → 79 (identification) were observed for the labeled internal standard (i.e., the 13C stable isotope labels are associated with the pinacolyl group of 13C6-PMPA). MRM transitions of m/z 137 → 79 (quantification) and m/z 137 → 77 (identification) were observed for IMPA as well as the internal standard transitions of m/z 144 → 95 (quantification) and 144 → m/z 79 (identification). Similar fragments were observed for both analytes as a result of the loss of the side chain from the phosphonyl moiety.

Figure 2

Figure 2. Parent ion fragmentation observed in negative ESI-MS-MS analysis for (A) PMPA and (B) IMPA.

High Resolution Image
Download MS PowerPoint Slide
Figure 3 shows representative chromatograms of prepared hair samples. PMPA eluted at approximately 3.8 min and IMPA at approximately 3.5 min. The isotopically labeled internal standards (not shown) coelute with their corresponding nonlabeled analyte. No significant tailing was observed in the IMPA or PMPA spiked hair. The method was very selective, as shown by the lack of coeluting chromatographic peaks for both analytes in the blanks. In fact, no other peaks were observed over 2–10 min for the chromatographic method. A peak corresponding to the void volume of the chromatographic system (not shown) does not interfere with the PMPA or IMPA. No degradation of the aqueous analyte or internal standard solutions used for preparing hair samples was observed over the storage term.

Figure 3

Figure 3. Representative chromatograms of PMPA and IMPA spiked hair (near LODs) samples (upper traces) as compared to saline exposed hair samples (lower traces). Internal standard response is not shown.

High Resolution Image
Download MS PowerPoint Slide

Calibration and Quantification

Calibration curves for PMPA were prepared in hair with an initial concentration range of 0.15–150 μg/kg. Calibrators with a concentration of 0.15 μg/kg did not satisfy the inclusion requirements and were excluded from the calibration range, resulting in a linear range of 0.3–150 μg/kg. Similar calibration curves were prepared for IMPA, with initial concentrations from 0.75 to 750 μg/kg. For IMPA, standard concentrations of 0.75, 1.5, and 3.0 μg/kg did not satisfy the calibration requirements, resulting in a linear range of 7.5–750 μg/kg. While the linear range for PMPA is slightly larger than that of IMPA, both analytes have linear ranges of at least 2 orders of magnitude, which is typical for analysis of biological samples. (66, 67) Correlation coefficients (R2) ranged from 0.9973 to 0.9996 and 0.9955 to 0.9999 for IMPA and PMPA, respectively. The relatively consistent R2 values show good linearity over the 3 days of QC analysis. For IMPA and PMPA, the slopes of the calibration curves ranged from 0.00473 to 0.00518 and 0.04291 to 0.05491, respectively.

LOD, Accuracy, and Precision

LODs were evaluated from spiked hair samples for PMPA and IMPA and are reported in Table 3, along with the accuracy and precision. Considering the amount of hair and the volume of solvent used to extract the hair, the LODs correspond to 100 pg/mL and 5 ng/mL for PMPA and IMPA, respectively. Therefore, the method presented here achieved comparable or lower detection limits than similar methods for AMPA analysis from biological samples. (63, 68-70)
Table 3. Accuracy, Precision, LOD, and Recovery of IMPA and PMPA from Spiked Hair Samples
    intra-assayinterassay
analyteLOD (μg/kg)QC concn (μg/kg)recovery (%)precision (% RSD)aaccuracy (%)aprecision (% RSD)baccuracy (%)b
IMPA7.520418.7100 ± 10.08.6100 ± 0.9
100434.3100 ± 4.54.2100 ± 4.7
500422.6100 ± 4.04.3100 ± 5.3
PMPA0.1513811.2100 ± 13.412.3100 ± 14.0
53519.4100 ± 12.56.4100 ± 0.1
20376.4100 ± 16.16.2100 ± 2.4
a

QC method validation (N = 5) for day 3.

b

Mean of three different days of QC method validation (N = 15).

QC standards at low, medium, and high concentrations were evaluated over 3 days of analysis to assess intra- and interassay accuracy and precision. The precision and accuracy were acceptable for both PMPA and IMPA for the concentrations tested but proved much better for IMPA. The intra-assay precision was 11% or less while the interassay precision for IMPA was <9% RSD. IMPA accuracy measurements were within ±10% and ±6% of the nominal QC concentrations for intra- and interassay experiments, respectively. PMPA produced a maximum intra-assay precision of 19% RSD, and an interassay precision of 13% RSD. The accuracy was within ±16% and ±14% of nominal concentrations for intra- and interassay studies, respectively.

Short-Term Stability, Recovery, and Matrix Effects

Short-term stability of AMPAs was evaluated in the autosampler over a 24 h period. Prepared IMPA and PMPA samples at high QC concentrations were stable in the autosampler for at least 24 h. IMPA and PMPA showed accuracy within 12% and 14%, respectively, when compared to the initial analysis of the study (i.e., time zero).
Recovery of IMPA and PMPA were generally consistent across the three concentrations tested (low, medium, and high QCs). IMPA recovery ranged from 41 to 43%, while recovery of PMPA was 35 to 38%. It is observed in the literature that AMPAs analyzed out of other biological matrixes sometimes yield higher recoveries. For example, Hayes et al. (69) demonstrated 95–211% recovery of various AMPAs from saliva samples. However, this is not always the case. Fredriksson et al. (9) showed 58–102% recovery of AMPAs in serum and urine samples, and Katagi et al. (70) only recovered 47–89% of AMPAs from human serum. Comparatively, in analyzing pesticide exposure from hair samples, Tutudaki and co-workers achieved recoveries of 69% from rats and rabbits. (61, 62) Margariti and Tsatsakis (56) analyzed dialkyl phosphate metabolites from human hair with 56–108% recovery. While the recoveries achieved in this study are not as high as hoped, they still allowed detection of AMPAs from hair at low limits of detection. Increasing recoveries may be an area of future improvement for the method and may potentially be achieved by modifying the extractant.
Matrix effects were assessed by comparison of spiked aqueous and hair samples. Matrix effects were most prominent for PMPA. The slope of the calibration curve made from the hair samples was 31% of the slope of the calibration curve from the aqueous samples. Although not as prevalent, matrix effects were also observed in the analysis of IMPA. When comparing slopes of the IMPA calibration curves, the slope from the hair samples was 70% of that of the aqueous samples. Although matrix effects were significant for the method presented, the internal standard accurately corrected for these effects, as confirmed by the accuracy of the method. The matrix effects observed may partially account for the low recoveries observed, especially for PMPA.

Verification of Nerve Agent Exposure

The method described here was applied to the analysis of hair samples collected from soman (GD) exposed rats. The exposed hair samples were received from USAMRICD early in method development and required storage until the method was developed and validated. Because the storage of hair samples after an exposure has not been studied, it was unclear as to whether the analyte would be stable in the stored matrix at the chosen storage conditions (−80 °C) or if it would be quantifiable when analyzed by LC–MS/MS. Figure 4 shows chromatograms from the initial analysis (3.5 years after collection) of both saline and GD exposed rats. The figure shows an obvious PMPA peak at approximately 3.9 min in the GD exposed samples, while the saline exposed samples show no signs of PMPA at that retention time. It is very likely that the PMPA seen in the hair is a result of soman in the bloodstream hydrolyzing to PMPA and subsequently being deposited into the hair as the blood nourishes active hair follicles. Although it could be proposed that PMPA may originate from the evaporation of soman, deposition onto the hair of the animal, and subsequent conversion to PMPA during the original exposure, it is highly unlikely. The administration of soman was performed as a subcutaneous injection in the hind leg of the animals by trained personnel in a well-ventilated space. This minimized the chance of evaporation of the soman, and even if a small amount soman did evaporate from the solution inside the syringe, it would likely be swept out of the area before it could deposit on the hair. Another alternative possibility for PMPA detection on the hair is contamination of the hair by urine containing PMPA. It is well-known that soman exposure results in urinary excretion of PMPA (Table 1). While it is possible that if urine came in contact with the hair during the first few days after exposure PMPA could have deposited on the outside of the hair, it is highly unlikely that this type of contamination could occur on the back of the animal (i.e., the hair analyzed was removed from the back). Moreover, the washing procedure described in the Hair Samples section should have removed any external contamination of PMPA prior to analysis by either route of PMPA contamination (i.e., soman vapor contamination or urinary contamination).

Figure 4

Figure 4. Chromatographic analysis of PMPA from exposed rats collected 1 month after exposure, stored, and then analyzed 3.5 years following exposure. PMPA is clearly evident above the LOD in all the GD exposed rats (calculated concentrations ranged from below the LLOQ up to 11.7 μg/kg) and not present in the hair of saline exposed rats.

High Resolution Image
Download MS PowerPoint Slide
A second analysis of this hair was performed approximately 2 years after the initial analysis (5.5 years after collection). This analysis resulted in the saline-exposed rat hair samples showing no signals for PMPA, while the GD exposed samples show a PMPA peak for all samples but one. These results indicate that the analyte can generally be detected in the hair matrix up to 5.5 years with storage at −80 °C. Follow-up studies will be undertaken in the near future to address the stability of the PMPA in hair under a variety of conditions to simulate the typical environmental conditions hair may encounter. Additional follow-on studies could include vapor or percutaneous exposure to the agent (i.e., subcutaneous exposure does not approximate a real-life exposure event) and allowing more than 30 days to lapse after exposure but before sample collection.

Conclusion

Click to copy section linkSection link copied!
Hair was examined as a matrix for determining past exposure to CWAs. PMPA and IMPA were extracted from hair samples and analyzed by LC–MS/MS. The method produced low limits of detection, good precision and accuracy, and excellent stability. The method showed the ability to detect PMPA from exposed rats when collected 1 month after exposure and analyzed 3.5 years after exposure. Hair also showed the ability to preserve the metabolite under the storage conditions used in this study for over 5 years. Although analysis of CWA metabolites from hair via this technique is not appropriate as a universal method to determine exposure (i.e., it takes time for the hair to grow above the surface of the skin and typical analysis times are >24 h), it complements existing methods and could become the preferred method for verification of exposure if 10 or more days have elapsed after a suspected exposure.

Author Information

Click to copy section linkSection link copied!
  • Corresponding Author
    • Brian A. Logue - Department of Chemistry and Biochemistry, South Dakota State University, Avera Health and Science, Box 2202, Brookings, South Dakota 57007, United States;  Email: [email protected]
  • Authors
    • Amanda S. Appel - Department of Chemistry and Biochemistry, South Dakota State University, Avera Health and Science, Box 2202, Brookings, South Dakota 57007, United States
    • John H. McDonough - Pharmacology Branch, Research Division U.S. Army Medical Research Institute of Chemical Defense 3100 Ricketts Point Road, Aberdeen Proving Ground, Maryland 21010, United States
    • Joseph D. McMonagle - Pharmacology Branch, Research Division U.S. Army Medical Research Institute of Chemical Defense 3100 Ricketts Point Road, Aberdeen Proving Ground, Maryland 21010, United States
  • Notes
    The authors declare no competing financial interest.

Acknowledgment

Click to copy section linkSection link copied!

This research was supported by the Defense Threat Reduction Agency under Contract HDTRA-1-07-C0026, through the Medical Research and Materiel Command Broad Agency Announcement, and the South Dakota State University Research Support Fund. Animal studies were supported by the Defense Threat Reduction Agency–Joint Science and Technology Office, Medical S&T Division. We thank the National Science Foundation Major Research Instrumentation Program (Grant Number CHE-0922816), the state of South Dakota, and South Dakota State University for funding the AB SCIEX QTRAP 5500 LC–MS/MS. The LC–MS/MS instrumentation was housed in the South Dakota State University Campus Mass Spectrometry Facility, which was supported by the National Science Foundation/EPSCoR Grant No. 0091948 and the State of South Dakota. The authors would also like to thank the U.S. Army Medical Research Institute for Chemical Defense, including the laboratories of Carl D. Smith and Todd M. Myers for providing animal hair for testing. Additionally, the authors would like to thank Bruce Gray and Fred DeRoos at the University of South Dakota for assistance with preliminary work on a GC/MS/MS method for the soman and sarin metabolites. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of Defense, the National Science Foundation, or the State of South Dakota.

References

Click to copy section linkSection link copied!

This article references 70 other publications.

  1. 1
    Sidell, F. R.; Tdkafuji, E. T.; Franz, D. R., Eds. Medical Aspects of Chemical and Biological Warfare; Office of the Surgeon General: Falls Church, VA, 1997.
    Google Scholar
    There is no corresponding record for this reference.
  2. 2
    Munro, N. Environ. Health Perspect. 1994, 102, 18– 38 DOI: 10.1289/ehp.9410218
    Google Scholar
    There is no corresponding record for this reference.
  3. 3
    Brown, M. A.; Brix, K. A. J. Appl. Toxicol. 1998, 18, 393– 408 DOI: 10.1002/(SICI)1099-1263(199811/12)18:6<393::AID-JAT528>3.0.CO;2-0
    Google Scholar
    3
    Review of health consequences from high-, intermediate- and low-level exposure to organophosphorus nerve agents
    Brown, Mark A.; Brix, Kelley A.
    Journal of Applied Toxicology (1998), 18 (6), 393-408CODEN: JJATDK; ISSN:0260-437X. (John Wiley & Sons Ltd.)
    A review and discussion with 78 refs. Short and long-term health effects from exposure to organophosphorus (OP) military and insecticidal nerve agents are evaluated based on the abundant scientific literature published over five decades on health effects in humans (from human experimentation and occupational exposures) and in lab. animals. Four distinct health effects are identified: acute cholinergic toxicity; organophosphate-induced delayed neuropathy (OPIDN); subtle long-term neuropsychol. and neurophysiol. effects; and a reversible muscular weakness called "intermediate syndrome". Some effects are subtle and difficult to differentiate from health effects caused by other diseases or occupational exposures. Each effect has data suggesting threshold exposure levels below which it is unlikely to be clin. detectable. Therefore, meaningful interpretation of human and animal studies requires rigid exposure characterization. Because precise exposure levels are often difficult to reconstruct, a system for characterizing exposure is proposed based upon obsd. initial acute signs and symptoms, as high-level (definitive cholinergic poisoning); intermediate-level (threshold cholinergic effects including miosis, rhinorrhea or clin. measurable depression of cholinesterase); and low-level (no immediate clin. signs or symptoms) exposure. Threshold exposure levels for known long-term effects from OP nerve agent are at or above intermediate-level exposure. Long-term health effects seen at intermediate-level exposures or in many survivors of high-level exposure are subtle, detectable in exposed populations but not individuals, and not reported in individuals experiencing low-level exposure alone. Co-exposure to other pharmaceutical agents may promote or protect against health effects from OP nerve agents, but qual. they are the same effects seen with OP nerve agents alone. Thus, the system for characterizing exposure based on initial acute effects is also useful for evaluating health outcomes from co-exposure to OP nerve and other agents.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXnsFSrurw%253D&md5=7c4c693fa1d50f8e6450b24f8e617db9
  4. 4
    DeCaprio, A. P., Ed. Toxicologic Biomarkers; Taylor & Francis Group: New York, 2006.
    Google Scholar
    There is no corresponding record for this reference.
  5. 5
    Desoubries, C.; Chapuis-Hugon, F.; Bossée, A.; Pichon, V. J. Chromatogr. B: Anal. Technol. Biomed. Life Sci. 2012, 900, 48– 58 DOI: 10.1016/j.jchromb.2012.05.029
    Google Scholar
    5
    Three-phase hollow fiber liquid-phase microextraction of organophosphorous nerve agent degradation products from complex samples
    Desoubries, Charlotte; Chapuis-Hugon, Florence; Bossee, Anne; Pichon, Valerie
    Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences (2012), 900 (), 48-58CODEN: JCBAAI; ISSN:1570-0232. (Elsevier B.V.)
    Degrdn. products of chem. warfare agents are considered as important environmental and biol. markers of chem. attacks. Alkyl methylphosphonic acids (AMPAs), resulting from the fast hydrolysis of nerve agents, such as sarin and soman, and the methylphosphonic acid (MPA), final degrdn. product of AMPAs, were detd. from complex matrixes by using an emergent and miniaturized extn. technique, the hollow fiber liq.-phase microextn. (HF-LPME), before their anal. by liq. chromatog. coupled to mass spectrometry (LC-MS). After studying different conditions of sepn. in the reversed phase LC-MS anal., the sample treatment method was set up. The three-phase HF-LPME was carried out by using a porous polypropylene (PP) hollow fiber impregnated with 1-octanol that separates the donor and acceptor aq. media. Various extn. parameters were evaluated such as the vol. of the sample, the effect of the pH and the salt addn. to the sample, the pH of the acceptor phase, the extn. temp., the stirring speed of the sample, the immersion time in the org. solvent and the time of extn. The optimum conditions were applied to the detn. of MPA and five AMPAs in real samples, such as surface waters and urine. Compds. were extd. from a 3 mL acidified sample into only 6 μL of alk. water without any other pretreatment of the complex matrixes. Enrichment factors (EFs) higher than 170 were obtained for three less polar AMPAs. Limits of quantification (LOQs) in the 0.013-5.3 ng mL-1 range were obtained after microextn. of AMPAs from river water and in the range of 0.056-4.8 ng mL-1 from urine samples with RSD values between 1 and 9%.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XpsV2ntL8%253D&md5=161f83560980f4629232b5795cc7f240
  6. 6
    Rodin, I.; Braun, A.; Stavrianidi, A.; Baygildiev, T.; Shpigun, O.; Oreshkin, D.; Rybalchenko, I. J. Anal. Toxicol. 2015, 39, 69– 74 DOI: 10.1093/jat/bku119
    Google Scholar
    6
    'Dilute-and-shoot' RSLC-MS-MS method for fast detection of nerve and vesicant chemical warfare agent metabolites in urine
    Rodin Igor; Braun Arcady; Stavrianidi Andrey; Baygildiev Timur; Shpigun Oleg; Oreshkin Dmitry; Rybalchenko Igor
    Journal of analytical toxicology (2015), 39 (1), 69-74 ISSN:.
    A sensitive screening method based on fast liquid chromatography tandem mass-spectrometry (RSLC-MS-MS) has shown the feasibility of separation and detection of low concentration β-lyase metabolites of sulfur mustard and of nerve agent phosphonic acids in urine. The analysis of these compounds is of interest because they are specific metabolites of the chemical warfare agents (CWAs), sulfur mustard (HD), sarin (GB), soman (GD), VX and Russian VX (RVX). The 'dilute-and-shoot' RSLC-MS-MS method provides a sensitive and direct approach for determining CWA exposure in non-extracted non-derivatized samples from urine. Chromatographic separation of the metabolites was achieved using a reverse phase column with gradient mobile phases consisting of 0.5% formic acid in water and acetonitrile. Identification and quantification of species were achieved using electrospray ionization-tandem mass-spectrometry monitoring two precursor-to-product ion transitions for each compound. The method demonstrates linearity over at least two orders of magnitude and had detection limits of 0.5 ng/mL in urine.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC2M3hsFKlsQ%253D%253D&md5=094e0aedfc3d1bfd3f6a059bec6d281a
  7. 7
    Shih, M.; McMonagle, J.; Dolzine, T.; Gresham, V. J. Appl. Toxicol. 1994, 14, 195– 199 DOI: 10.1002/jat.2550140309
    Google Scholar
    7
    Metabolite pharmacokinetics of soman, sarin and GF in rats and biological monitoring of exposure to toxic organophosphorus agents
    Shih, Ming L.; McMonagle, Joseph D.; Dolzine, Theodore W.; Gresham, Vincent C.
    Journal of Applied Toxicology (1994), 14 (3), 195-9CODEN: JJATDK; ISSN:0260-437X.
    This study reports on the pharmacokinetics of the elimination of the metabolites of three toxic organophosphorus compds. (soman, sarin and GF). Urine, blood and lung tissue were collected from rats dosed s.c. at 75 μg kg-1. Urinary excretion of the metabolite was the major elimination route for these three compds. The major differences among them were primarily the extent and rate of excretion. The hydrolyzed form, alkylmethylphosphonic acid, was the single major metabolite formed and excreted in urine by a non-saturable mechanism. Nearly total recoveries of the given doses for sarin and GF in metabolite form were obtained from the urine. The terminal elimination half-lives in urine were 3.7 ± 0.1 and 9.9 ± 0.8 h for sarin and GF, resp. Soman metabolite showed a biphasic elimination curve with terminal half-lives of 18.5 ± 2.7 and 3.6 ± 2.2 h. Soman was excreted at a slower rate with a recovery of only 62%. Lung was the major organ of accumulation for soman. In blood the toxic agents were concd. more in red blood cells than in plasma. The acid metabolites can serve as a better chem. marker for monitoring organophosphorus exposure in humans via their higher concn. and longer half-life in urine than the parent compds.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2cXkt1yrtrY%253D&md5=ea0bce98d782d4c7fd5af48ee876144a
  8. 8
    Minami, M.; Hui, D.; Katsumata, M.; Inagaki, H.; Boulet, C. J. Chromatogr., Biomed. Appl. 1997, 695, 237– 244 DOI: 10.1016/S0378-4347(97)00203-X
    Google Scholar
    8
    Method for the analysis of the methylphosphonic acid metabolites of sarin and its ethanol-substituted analog in urine as applied to the victims of the Tokyo sarin disaster
    Minami, Masayasu; Hui, Da-Mei; Katsumata, Masao; Inagaki, Hirofumi; Boulet, Camille A.
    Journal of Chromatography B: Biomedical Sciences and Applications (1997), 695 (2), 237-244CODEN: JCBBEP; ISSN:0378-4347. (Elsevier)
    An anal. method for the methylphosphonic acid metabolites of sarin in urine using trimethylsilyl derivatization and flame photometric detection is described in this report. Authentic ref. stds. of iso-Pr methylphosphonic acid (IMPA) and Et methylphosphonic acid (EMPA) as well as methylphosphonic acid were employed to est. the concn. in human urine. A sample pretreatment procedure was developed for urine using a column of cation-loaded ion-exchange resins (Ag+-, Ba2+- or H+-Dowex) and adjusting the pH of the eluate from the column to 3.75-3.85 improved recovery of the target compds. The eluate was evapd. to dryness under vacuum prior to trimethylsilylation, to remove water and any hydroxy- or amino-carrying volatile substances. The sarin metabolites, because of their low volatility, were concd. and could be derivatized for anal. The use of synthesized authentic sarin and ethylsarin metabolites, i.e., IMPA and EMPA, made it possible to establish the necessary sample pretreatment procedures for derivatization and gas chromatog.-flame photometric detection (GC-FPD) anal. The detection limits were 0.025 ppm both for EMPA and IMPA, and 0.625 μM for MPA, resp. This method can be useful for estg. the exposure level to sarin by assaying the metabolites in urine and it is applicable to a large nos. of samples.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXks12lu7w%253D&md5=378454be3ba8b20787cc2a4ced0847df
  9. 9
    Fredriksson, S.-A.; Hammarstrom, L.-G.; Henriksson, L.; Lakso, H.-A. J. Mass Spectrom. 1995, 30, 1133– 1143 DOI: 10.1002/jms.1190300810
    Google Scholar
    9
    Trace determination of alkyl methylphosphonates in environmental and biological samples using gas chromatography/negative-ion chemical ionization mass spectrometry and tandem mass spectrometry
    Fredriksson, Sten-Aake; Hammerstroem, Lars-Gunnar; Henriksson, Liselott; Lakso, Hans-Aake
    Journal of Mass Spectrometry (1995), 30 (8), 1133-43CODEN: JMSPFJ; ISSN:1076-5174. (Wiley)
    Alkyl methylphosphonates (I) are metabolites and primary hydrolysis products of the organophosphorus nerve agents listed in the Chem. Weapons Convention. Gas chromatog./neg.-ion chem. ionization mass spectrometry and tandem mass spectrometry (GC/NICI-MS and GC/NICI-MS/MS) were used for the detn. of I as their pentafluorobenzyl esters. Extremely high sensitivity was obtained and low attogram amts. could be detected by GC/NICI-MS. Ion-exchange chromatog. was employed for selective isolation and enrichment of I in serum, urine, water and soil samples. Collision-induced dissocn. (CID) of the single methylphosphonate anion peak from NICI of the pentafluorobenzyl ester produced fragment ions specific for the methylphosphonate structure, allowing pos. identification of I. CID conditions optimized for structure information and for sensitivity were investigated. The improved selectivity of GC/MS/MS allows the detection of femtogram amts. of I in samples where chem. background inhibits detection by GC/MS.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2MXnsFajtb0%253D&md5=fbb6ca0442228686df72c9b04a4013cb
  10. 10
    Noort, D.; Hulst, A.; Platenburg, D.; Polhuijs, M.; Benschop, H. Arch. Toxicol. 1998, 72, 671– 675 DOI: 10.1007/s002040050559
    Google Scholar
    10
    Quantitative analysis of O-isopropyl methylphosphonic acid in serum samples of Japanese citizens allegedly exposed to sarin: estimation of internal dosage
    Noort, Daan; Hulst, Albert G.; Platenburg, Dominique H. J. M.; Polhuijs, Martine; Benschop, Hendrik P.
    Archives of Toxicology (1998), 72 (10), 671-675CODEN: ARTODN; ISSN:0340-5761. (Springer-Verlag)
    A convenient and rapid micro-anion exchange liq. chromatog. (LC) tandem electrospray mass spectrometry (MS) procedure was developed for quant. anal. in serum of O-iso-Pr methylphosphonic acid (IMPA), the hydrolysis product of the nerve agent sarin. The mass spectrometric procedure involves neg. or pos. ion electrospray ionization and multiple reaction monitoring (MRM) detection. The method could be successfully applied to the anal. of serum samples from victims of the Tokyo subway attack and of an earlier incident at Matsumoto, Japan. IMPA levels ranging from 2 to 135 ng/mL were found. High levels of IMPA appear to correlate with low levels of residual butyrylcholinesterase activity in the samples and vice versa. Based on our analyses, the internal and exposure doses of the victims were estd. In several cases, the doses appeared to be substantially higher than the assumed LDs in man.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXmvFCqtLo%253D&md5=4dd87f7705d0707e52f27fa9e9002066
  11. 11
    Evans, R.; Jakubowski, E.; Muse, W.; Matson, K.; Hulet, S.; Mioduszewski, R.; Thomson, S.; Totura, A.; Renner, J.; Crouse, C. J. Anal. Toxicol. 2008, 32, 78– 85 DOI: 10.1093/jat/32.1.78
    Google Scholar
    11
    Quantification of Sarin and Cyclosarin Metabolites Isopropyl Methylphosphonic Acid and Cyclohexyl Methylphosphonic Acid in Minipig Plasma Using Isotope-Dilution and Liquid Chromatography- Time-of-Flight Mass Spectrometry
    Evans, R. A.; Jakubowski, E. M.; Muse, W. T.; Matson, K.; Hulet, S. W.; Mioduszewski, R. J.; Thomson, S. A.; Totura, A. L.; Renner, J. A.; Crouse, C. L.
    Journal of Analytical Toxicology (2008), 32 (1), 78-85CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
    An anal. method for detg. iso-Pr methylphosphonic acid (IMPA) and cyclohexyl methylphosphonic acid (CMPA), the metabolic hydrolysis products of toxic organophosphorus nerve agents iso-Pr methylphosphonofluoridate (sarin, GB) and cyclohexyl methylphosphonofluoridate (cyclosarin, GF), resp., has been developed and validated using high-performance liq. chromatog.-mass spectrometry with neg. ion electrospray ionization with time-of-flight detection (LC-ESI-MS-TOF). The linear range of quantitation was 5 to 125 ng/mL in plasma with a method detection limit of 2 ng/mL for each compd. This method was developed to det. the amt. of metabolic hydrolysis that was formed during and after nerve agent exposure in minipigs to account for a major pathway of GB and GF elimination that had not been previously characterized in the bloodstream, particularly during low-level whole-body inhalation expts. Metabolic hydrolysis accounted for 70% to 90% of the recoverable agent in the bloodstream during exposure, when compared to both unbound and cholinesterase bound agent recovered by fluoride ion reactivation anal. for the same samples. The estd. half-life of IMPA and CMPA in plasma was detd. to be 44 and 61 min, resp. The method utilizes the mass selectivity of LC-ESI-MS-TOF using a bench-top instrument to achieve a detection limit that is consistent with reported LC-MS-MS methods analyzing blood samples. (c) 2008 Preston Publications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1cXhtFertr0%253D&md5=d7a321106c5a2fccd2647f05b08a462c
  12. 12
    Røen, B. T.; Sellevåg, S. R.; Lundanes, E. Anal. Chem. 2014, 86, 11833– 11840 DOI: 10.1021/ac503408x
    Google Scholar
    There is no corresponding record for this reference.
  13. 13
    Abney, C. W.; Knaack, J. L.; Ali, A. A.; Johnson, R. C. Chem. Res. Toxicol. 2013, 26, 775– 782 DOI: 10.1021/tx4000717
    Google Scholar
    There is no corresponding record for this reference.
  14. 14
    van der Meer, J.; Trap, H.; Noort, D.; van der Schans, M. J. Chromatogr. B: Anal. Technol. Biomed. Life Sci. 2010, 878, 1320– 1325 DOI: 10.1016/j.jchromb.2010.02.019
    Google Scholar
    14
    Comprehensive gas chromatography with Time of Flight MS and large volume introduction for the detection of fluoride-induced regenerated nerve agent in biological samples
    van der Meer, J. A.; Trap, H. C.; Noort, D.; van der Schans, M. J.
    Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences (2010), 878 (17-18), 1320-1325CODEN: JCBAAI; ISSN:1570-0232. (Elsevier B.V.)
    Recently, several methods were developed to verify exposure to nerve agents. Most of these methods, such as the fluoride reactivation technique and the anal. of inhibited phosphonylated butyrylcholinesterase (BuChE), are based on mass spectrometry. The high specificity of the mass spectrometer might also imply a disadvantage, because the acquisition mass, i.e. the identity of the analyte must be known beforehand to direct the MS anal. in the most sensitive mode. In real cases, the identity of the nerve agent is not always known beforehand and the mass spectrometer should be operated in a scanning mode, with the consequence that sensitivity of the method will be lower. Comprehensive GC, or GC × GC, is a technique which offers enhanced sepn. The implied larger selectivity of the GC sepn. allows mass spectrometry to be conducted in a less specific, scanning, mode. By the use of this configuration, the identity of the nerve agent does not have to be known beforehand but can be traced. In order to be able to detect lower concns. and assess lower exposure levels, a large vol. injection technique was developed allowing sample sizes up to 100 μL. The technique was tested with plasma samples that had been inhibited with various nerve agents. Subsequently, the cholinesterase-bound nerve agent was regenerated by the fluoride reactivation technique. Using the newly developed comprehensive GC-MS method it was possible to detect nerve agent at an exposure level of 1% BuChE inhibition, which is approx. 70 pg nerve agent/mL. These low exposure levels cannot be verified with a cholinesterase (ChE) activity assay. Moreover, the identity of the regenerated nerve agent was verified by the mass spectrum that was generated by the TOF mass spectrometer. This paper presents a technique able to deliver full-scan data on the anal. of nerve agents in biomedical samples at relevant exposure levels (1% BuChE inhibition). This full-scan data meets for a large part the forensic requirements that are in place for the anal. of biomedical samples in the context of alleged use of Chem. Warfare Agents.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXlt1GmtLc%253D&md5=991c2e3c88602b0f612852b7f5fbbb51
  15. 15
    Polhuijs, M.; Langenberg, J. P.; Benschop, H. P. Toxicol. Appl. Pharmacol. 1997, 146, 156– 161 DOI: 10.1006/taap.1997.8243
    Google Scholar
    15
    New method for retrospective detection of exposure to organophosphorus anticholinesterases: application to alleged sarin victims of Japanese terrorists
    Polhuijs, Martine; Langenberg, Jan P.; Benschop, Hendrik P.
    Toxicology and Applied Pharmacology (1997), 146 (1), 156-161CODEN: TXAPA9; ISSN:0041-008X. (Academic)
    With regard to detection of exposure to anticholinesterase, the presently used methods have the disadvantage that they cannot detect either low-level exposures with certainty or the structure of the agent and the extent of poisoning. 4In principle, organophosphate-inhibited butyrylcholinesterase in human plasma is the most persistent and abundant source for biomonitoring of exposure to organophosphate anticholinesterases. Fluoride ions reactivate the inhibited enzyme readily at pH 4, converting the organophosphate moiety into the corresponding phosphofluoridate. Subsequent quantitation of the latter product provides a reliable, highly sensitive and retrospective method for detection of exposure to, or handling of, organophosphates such as nerve agents and organophosphorus pesticides. The authors applied the new procedure to serum samples from victims of the Tokyo subway attack by the AUM Shinriyko sect and from an earlier incident at Matsumoto. In serum of 10 of 11 victims from the Tokyo incident and of 2 of the 7 samples from the Matsumoto incident, reactivation with fluoride ions yielded sarin concns. in the range of 0.2-4.1 ng/mL serum. Evidently, these victims had been exposed to an organophosphate with the structure PriO(CH3)P(O)X, presumably with X = F (sarin). Several applications of the new procedure to establish nerve agent and/or organophosphate (OP) pesticide exposure can be envisaged, e.g., (i) in biomonitoring of exposure for health surveillance of those handling organophosphates, (ii) in cases of alleged exposure to nerve agents and/or OP pesticides in armed conflict situations or terrorist attacks, (iii) in medical treatment of intoxication, and (i.v.) in forensic cases against suspected terrorists that may have handled anticholinesterases.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXmt1Wgsb0%253D&md5=0f845cde04dad82b9ec8be1779d7c5e1
  16. 16
    Adams, T.; Capacio, B.; Smith, J.; Whalley, C.; Korte, W. Drug Chem. Toxicol. 2005, 27, 77– 91 DOI: 10.1081/DCT-120027901
    Google Scholar
    There is no corresponding record for this reference.
  17. 17
    Lee, J. Y.; Lee, Y. H. Int. J. Anal. Mass Spectrom. Chromatogr. 2014, 2, 65 DOI: 10.4236/ijamsc.2014.23007
    Google Scholar
    There is no corresponding record for this reference.
  18. 18
    Sporty, J. L.; Lemire, S. W.; Jakubowski, E. M.; Renner, J. A.; Evans, R. A.; Williams, R. F.; Schmidt, J. G.; Schans, M. J. v. d.; Noort, D.; Johnson, R. C. Anal. Chem. 2010, 82, 6593– 6600 DOI: 10.1021/ac101024z
    Google Scholar
    There is no corresponding record for this reference.
  19. 19
    Carter, M. D.; Crow, B. S.; Pantazides, B. G.; Watson, C. M.; Thomas, J. D.; Blake, T. A.; Johnson, R. C. Anal. Chem. 2013, 85, 11106– 11111 DOI: 10.1021/ac4029714
    Google Scholar
    There is no corresponding record for this reference.
  20. 20
    Crow, B. S.; Pantazides, B. G.; Quiñones-González, J.; Garton, J. W.; Carter, M. D.; Perez, J. W.; Watson, C. M.; Tomcik, D. J.; Crenshaw, M. D.; Brewer, B. N. Anal. Chem. 2014, 86, 10397– 10405 DOI: 10.1021/ac502886c
    Google Scholar
    There is no corresponding record for this reference.
  21. 21
    Fidder, A.; Hulst, A.; Noort, D.; de Ruiter, R.; van der Schans, M.; Benschop, H.; Langenberg, J. Chem. Res. Toxicol. 2002, 15, 582– 590 DOI: 10.1021/tx0101806
    Google Scholar
    There is no corresponding record for this reference.
  22. 22
    Che, M. M.; Conti, M.; Boylan, M.; Sciuto, A. M.; Gordon, R. K.; Nambiar, M. P. Inhalation Toxicol. 2008, 20, 821– 828 DOI: 10.1080/08958370802050957
    Google Scholar
    22
    Blood and Bronchoalveolar Lavage Fluid Acetylcholinesterase Levels Following Microinstillation Inhalation Exposure to Sarin in Guinea Pigs
    Che, Magnus M.; Conti, Michele; Boylan, Megan; Sciuto, Alfred M.; Gordon, Richard K.; Nambiar, Madhusoodana P.
    Inhalation Toxicology (2008), 20 (9), 821-828CODEN: INHTE5; ISSN:0895-8378. (Informa Healthcare)
    The authors detd. acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition in the bronchoalveolar lavage fluid (BALF) following inhalation exposure to chem. threat nerve agent (CTNA) sarin. Age- and wt.-matched male guinea pigs were exposed to 5 different doses of sarin (169.3, 338.7, 508, 677.4, and 846.5 mg/m3) using a microinstillation inhalation exposure technique for 4 min. The technique involves aerosolization of the agent in the trachea using a microcatheter with a center hole that delivers the agent and multiple peripheral holes that pumps air to aerosolize the agent at the tip. Animals exposed to higher doses of sarin occasionally developed seizures and succumbed to death within 15 min after exposure. The LCt50 for sarin using the microinstillation technique was detd. to be close to 677.4 mg/m3. Ear blood AChE activity showed a dose-dependent inhibition at 15 min postexposure. The inhibition of blood AChE remained const. over 35 and 55 min after sarin exposure indicating that there was no lung depot effect. Cardiac blood AChE and butyrylcholinesterase (BChE) activity in surviving animals euthanized at 24 h postexposure showed a dose-dependent inhibition with an inhibition of 60% at 677.4 and 846.5 mg/m3 sarin exposure. AChE and BChE activity in bronchoalveolar lavage fluid (BALF) showed a slight increase at 338.7-677.4 mg/m3 sarin exposure but a marginal inhibition at 169.3 mg/m3. In contrast, the AChE protein levels detd. by immunoblotting showed an increase at 169.3 mg/m3 in the BALF. The BALF protein level, a biomarker of lung injury, was increased maximally at 338.7 mg/m3 and that increase was dropped with an increase in the dose of sarin. The BALF protein levels correlated with the AChE and BChE activity. These data suggest that sarin microinstillation inhalation exposure results in respiratory toxicity and lung injury characterized by changes in lavage AChE, BChE, and protein levels.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1cXoslWqtbk%253D&md5=2ab6248389a63391554448f205726996
  23. 23
    Read, R.; Riches, J.; Stevens, J.; Stubbs, S.; Black, R. Arch. Toxicol. 2010, 84, 25– 36 DOI: 10.1007/s00204-009-0473-4
    Google Scholar
    23
    Biomarkers of organophosphorus nerve agent exposure: comparison of phosphylated butyrylcholinesterase and phosphylated albumin after oxime therapy
    Read, Robert W.; Riches, James R.; Stevens, Jacqueline A.; Stubbs, Sarah J.; Black, Robin M.
    Archives of Toxicology (2010), 84 (1), 25-36CODEN: ARTODN; ISSN:0340-5761. (Springer)
    Organophosphorus nerve agents inhibit the activity of cholinesterases by phosphylation of the active site serine. In addn., sarin, cyclosarin, soman and tabun have been shown to phosphylate a tyrosine residue in albumin. Therapies against nerve agent poisoning include the use of oximes to reactivate inhibited cholinesterases by displacement of the phosphyl moiety and hence detectable levels of adducts with cholinesterases may be reduced. Adducts with tyrosine have been shown to be persistent in the guinea pig in the presence of oxime therapy. Plasma samples obtained from an animal study aimed at improving therapy against nerve agent poisoning were used to compare the suitability of tyrosine and butyrylcholinesterase (BuChE) adducts as biomarkers of nerve agent exposure after treatment with therapeutic oximes. Under the terms of the project licence, these samples could be collected only on death of the animal, which occurred within hours of exposure or when culled at 23 or 24 days. Tyrosine adducts were detected in all samples collected following intra-muscular administration of twice the LD50 dose of the resp. nerve agent. Aged BuChE adducts were detected in samples collected within a few hours after administration of soman and tabun, but not after 23 or 24 days. No BuChE adducts were detected in animals exposed to sarin and cyclosarin where samples were collected only after 23 or 24 days.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXhtlanu7fO&md5=f0bd78020cc8453e483ea425eb30726f
  24. 24
    Bao, Y.; Liu, Q.; Chen, J.; Lin, Y.; Wu, B.; Xie, J. J. Chromatogr. A 2012, 1229, 164– 171 DOI: 10.1016/j.chroma.2012.01.032
    Google Scholar
    There is no corresponding record for this reference.
  25. 25
    Chen, S.; Zhang, J.; Lumley, L.; Cashman, J. R. J. Pharmacol. Exp. Ther. 2013, 344, 531– 541 DOI: 10.1124/jpet.112.201368
    Google Scholar
    25
    Immunodetection of serum albumin adducts as biomarkers for organophosphorus exposure
    Chen, Sigeng; Zhang, Jun; Lumley, Lucill; Cashman, John R.
    Journal of Pharmacology and Experimental Therapeutics (2013), 344 (2), 531-541CODEN: JPETAB; ISSN:1521-0103. (American Society for Pharmacology and Experimental Therapeutics)
    A major challenge in organophosphate (OP) research has been the identification and utilization of reliable biomarkers for the rapid, sensitive, and efficient detection of OP exposure. Although Tyr 411 OP adducts to human serum albumin (HSA) have been suggested to be one of the most robust biomarkers in the detection of OP exposure, the anal. of HSA-OP adduct detection has been limited to techniques using mass spectrometry. Herein, we describe the procurement of two monoclonal antibodies (mAb-HSA-GD and mAb-HSA-VX) that recognized the HSA Tyr 411 adduct of soman (GD) or S-[2-(diisopropylamino)ethyl]-O-Et methylphosphonothioate (VX), resp., but did not recognize nonphosphonylated HSA. We showed that mAb-HSA-GD was able to detect the HSA Tyr 411 OP adduct at a low level (i.e., human blood plasma treated with 180 nM GD) that could not be detected by mass spectrometry. MAb-HSA-GD and mAb-HSA-VX showed an extremely low-level detection of GD adducted to HSA (on the order of picograms). MAb-HSA-GD could also detect serum albumin OP adducts in blood plasma samples from different animals administered GD, including rats, guinea pigs, and monkeys. The ability of the two antibodies to selectively recognize nerve agents adducted to serum albumin suggests that these antibodies could be used to identify biomarkers of OP exposure and provide a new biol. approach to detect OP exposure in animals.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXhsFKhsrs%253D&md5=aa629bba77bcf91bb175e1469c55e4c9
  26. 26
    Williams, N.; Harrison, J.; Read, R.; Black, R. Arch. Toxicol. 2007, 81, 627– 639 DOI: 10.1007/s00204-007-0191-8
    Google Scholar
    26
    Phosphylated tyrosine in albumin as a biomarker of exposure to organophosphorus nerve agents
    Williams, Nichola H.; Harrison, John M.; Read, Robert W.; Black, Robin M.
    Archives of Toxicology (2007), 81 (9), 627-639CODEN: ARTODN; ISSN:0340-5761. (Springer)
    The organophosphorus nerve agents sarin, soman, cyclosarin and tabun phosphylate a tyrosine residue on albumin in human blood. These adducts may offer relatively long-lived biol. markers of nerve agent exposure that do not 'age' rapidly, and which are not degraded by therapy with oximes. Sensitive methods for the detection of these adducts have been developed using liq. chromatog.-tandem mass spectrometry. Adducts of all four nerve agents were detected in the blood of exposed guinea pigs being used in studies to improve medical countermeasures. The tyrosine adducts with soman and tabun were detected in guinea pigs receiving therapy 7 days following s.c. administration of five times the LD50 dose of the resp. nerve agent. VX also forms a tyrosine adduct in human blood in vitro but only at high concns.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXosFarsLc%253D&md5=a288265a5ff20941a6392c4d597e701e
  27. 27
    Nagao, M.; Takatori, T.; Matsuda, Y.; Nakajima, M.; Iwase, H.; Iwadate, K. Toxicol. Appl. Pharmacol. 1997, 144, 198– 203 DOI: 10.1006/taap.1997.8110
    Google Scholar
    27
    Definitive evidence for the acute sarin poisoning diagnosis in the Tokyo subway
    Nagao, Masataka; Takatori, Takehiko; Matsuda, Yukimasa; Nakajima, Makoto; Iwase, Hirotaro; Iwadate, Kimiharu
    Toxicology and Applied Pharmacology (1997), 144 (1), 198-203CODEN: TXAPA9; ISSN:0041-008X. (Academic)
    A new method was developed to detect sarin hydrolysis products from the erythrocytes of 4 victims of sarin (isopropylmethylphosphonofluoridate) poisoning resulting from the terrorist attack on the Tokyo subway. Sarin-bound acetylcholinesterase (AChE) was solubilized from the erythrocyte membranes of sarin victims, digested with trypsin, the sarin hydrolysis products bound to AChE were released by alk. phosphatase digestion, and the digested sarin hydrolysis products were subjected to trimethylsilyl derivatization and detected by gas chromatog.-mass spectrometry. Isopropylmethylphosphonic acid, which is a sarin hydrolysis product, was detected in all sarin poisoning victims examd. and methylphosphonic acid, which is a sarin and soman hydrolysis product, was detd. in all victims. Postmortem examns. revealed no macroscopic and microscopic findings specific to sarin poisoning and sarin and its hydrolysis products were almost undetectable in their blood. Thus, the procedure described is useful for the forensic diagnosis of acute sarin poisoning.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXivFKhur4%253D&md5=eb701b0d8553559b49733a7c5ead7215
  28. 28
    Tsuchihashi, H.; Katagi, M.; Nishikawa, M.; Tatsuno, M. J. Anal. Toxicol. 1998, 22, 383– 388 DOI: 10.1093/jat/22.5.383
    Google Scholar
    28
    Identification of metabolites of nerve agent VX in serum collected from a victim
    Tsuchihashi, Hitoshi; Katagi, Munehiro; Nishikawa, Mayumi; Tatsuno, Michiaki
    Journal of Analytical Toxicology (1998), 22 (5), 383-388CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
    A human serum sample collected from a victim of the Osaka VX incident was analyzed according to our developed technique for metabolites of VX. Gas chromatog.-mass spectrometry (GC-MS) in full-scan electron impact and chem. ionization modes were used, and, for more reliable confirmation, GC-MS-MS was also employed. In the serum sample, both Et methylphosphonic acid and 2-(diisopropylaminoethyl) Me sulfide were detected. These results indicated that the techniques using GC-MS and GC-MS-MS were applicable to biol. samples such as serum. These results also provide the first documented, unequivocal identification of the specific metabolites of VX in victim's serum and, furthermore, clarify a part of the metabolic pathway of VX in the human body.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXlvFaru7s%253D&md5=3817821c5624ab1188335390d901cd36
  29. 29
    Nagao, M.; Takatori, T.; Matsuda, Y.; Nakajima, M.; Niijima, H.; Iwase, H.; Iwadate, K.; Amano, T. J. Chromatogr., Biomed. Appl. 1997, 701, 9– 17 DOI: 10.1016/S0378-4347(97)00355-1
    Google Scholar
    29
    Detection of sarin hydrolysis products from sarin-like organophosphorus agent-exposed human erythrocytes
    Nagao, Masataka; Takatori, Takehiko; Matsuda, Yukimasa; Nakajima, Makoto; Niijima, Hitoshi; Iwase, Hirotaro; Iwadate, Kimiharu; Amano, Toshikimi
    Journal of Chromatography B: Biomedical Sciences and Applications (1997), 701 (1), 9-17CODEN: JCBBEP; ISSN:0378-4347. (Elsevier)
    A sarin-like organophosphorus agent, [bis(iso-Pr methylphosphonate); BIMP], was synthesized. This agent has the same phosphonate group as sarin and also has the same anti-acetylcholinesterase activity potency as sarin. The ID50 and LD50 values of BIMP in mice after i.v. injection were 3.9 nM and 0.8 mg/kg, resp. The AChE activities of their red blood cells and brains were dose-dependently reduced by i.v. BIMP. After prepn. of exptl. BIMP-exposed human red blood cells, BIMP-bound acetylcholinesterase (AChE) was solubilized from erythrocyte membranes, purified by immunoaffinity chromatog., digested with trypsin, and the sarin hydrolysis products bound to AChE were released by alk. phosphatase digestion. The digested sarin hydrolysis products were subjected to trimethylsilyl (TMS) derivatization and detected by gas chromatog.-mass spectrometry. Iso-Pr methylphosphonic- and methylphosphonic acids, which are the sarin hydrolysis products, were detected in exptl. BIMP-exposed human red blood cells. This new method, which enables sarin's hydrolysis products to be detected in BIMP-exposed erythrocytes, is a useful tool for studying sarin-poisoning victims.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXntVOntrs%253D&md5=acc6ca592545c8d421f6b5e25a4617ff
  30. 30
    Bajgar, J. Occup. Environ. Med. 1992, 49, 648– 653 DOI: 10.1136/oem.49.9.648
    Google Scholar
    There is no corresponding record for this reference.
  31. 31
    Degenhardt, C.; Pleijsier, K.; van der Schans, M.; Langenberg, J.; Preston, K.; Solano, M.; Maggio, V.; Barr, J. J. Anal. Toxicol. 2004, 28, 364– 371 DOI: 10.1093/jat/28.5.364
    Google Scholar
    31
    Improvements of the Fluoride Reactivation Method for the Verification of Nerve Agent Exposure
    Degenhardt, Carla E. A. M.; Pleijsier, Kees; van der Schans, Marcel J.; Langenberg, Jan P.; Preston, Kerry E.; Solano, Maria I.; Maggio, V. L.; Barr, John R.
    Journal of Analytical Toxicology (2004), 28 (5), 364-371CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
    One of the most appropriate biomarkers for the verification of organophosphorus nerve agent exposure is the conjugate of the nerve agent to butyrylcholinesterase (BuChE). The phosphyl moiety of the nerve agent can be released from the BuChE enzyme by incubation with fluoride ions, after which the resulting organophosphonofluoridate can be analyzed with gas chromatog.-mass spectrometry (GC-MS). This paper describes recent improvements of the fluoride-induced reactivation in human plasma or serum samples by enhancing the sample prepn. with new solid-phase extn. cartridges and the MS anal. with large vol. injections. Anal. is performed with thermal desorption GC with either mass selective detection with ammonia chem. ionization or high-resoln. MS with electron impact ionization. The organophosphorus chem. warfare agents analyzed in this study are O-Et S-2-diisopropylaminoethyl methylphosphonothiolate, Et methylphosphonofluoridate, iso-Pr methylphosphonofluoridate (sarin, GB), O-Et N,N-dimethylphosphoramidocyanidate, Et N,N-dimethylphosphoramidofluoridate, and cyclohexyl methylphosphonfluoridate. Detection limits of approx. 10 pg/mL plasma were achieved for all analytes, which corresponds to 0.09% inhibition with GB on a sample with normal BuChE levels. (c) 2004 Preston Publications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXlsFKmsLk%253D&md5=f0e49a371114cc340a7b44841bf2eef8
  32. 32
    Wenthold, R.; Mahler, H.; Moore, W. J. Neurochem. 1974, 22, 941– 943 DOI: 10.1111/j.1471-4159.1974.tb04319.x
    Google Scholar
    32
    Half-life of acetylcholinesterase in mature rat brain
    Wenthold, R. J.; Mahler, H. R.; Moore, W. J.
    Journal of Neurochemistry (1974), 22 (6), 941-3CODEN: JONRA9; ISSN:0022-3042.
    The rate of degrdn. of acetylcholinesterase (EC 3.1.1.7) in mature rat cerebral cortex was detd. from the time course of the label introduced into the protein by 1 intraventricular injection of L-leucine-1-14C. The half-life of the enzyme was 2.84 days.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaE2cXltFOkt7Y%253D&md5=b322175ebf861e6ca5118083dda124f3
  33. 33
    Rotundo, R. L.; Fambrough, D. M. Cell 1980, 22, 583– 594 DOI: 10.1016/0092-8674(80)90368-2
    Google Scholar
    There is no corresponding record for this reference.
  34. 34
    Maxwell, D. M.; Castro, C. A.; De La Hoz, D. M.; Gentry, M. K.; Gold, M. B.; Solana, R. P.; Wolfe, A. D.; Doctor, B. P. Toxicol. Appl. Pharmacol. 1992, 115, 44– 49 DOI: 10.1016/0041-008X(92)90365-Y
    Google Scholar
    34
    Protection of rhesus monkeys against soman and prevention of performance decrement by pretreatment with acetylcholinesterase
    Maxwell, Donald M.; Castro, Carl A.; De la Hoz, Denise M.; Gentry, Mary K.; Gold, Mark B.; Solana, Richard P.; Wolfe, Alan D.; Doctor, Bhupendra P.
    Toxicology and Applied Pharmacology (1992), 115 (1), 44-9CODEN: TXAPA9; ISSN:0041-008X.
    The ability of acetylcholinesterase from fetal bovine serum (FBS AChE) to protect against soman, a highly toxic organophosphorus (OP) compd., was tested in Rhesus monkeys. I.v. administration of FBS AChE produced a minimal behavioral effect on the serial probe recognition task, a sensitive test of cognitive function and short-term memory. Pharmacokinetic studies of injected FBS AChE indicated a plasma half-life of 40 h for FBS AChE in monkeys. In vitro and in vivo titrn. of FBS AChE with soman produced a 1:1 stoichiometry between organophosphate-inhibited FBS AChE and the cumulative dose of the toxic stereoisomers of soman. Administration of FBS AChE protected monkeys against the lethal effects of up to 2.7 LD50 of soman and prevented any signs of organophosphate intoxication, e.g., excessive secretions, respiratory depression, muscle fasciculations, or convulsions. In addn., monkeys pretreated with FBS AChE were devoid of any behavioral incapacitation after soman challenge, as measured by the serial probe recognition task. Compared to the current multicomponent drug treatment against soman, which does not prevent the signs or the behavioral deficits resulting from OP intoxication, use of FBS AChE as a single pretreatment drug provides significantly effective protection against both the lethal and the behavioral effects of soman.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK38XltVGqs7c%253D&md5=7884cbb25abd24f3d27daff9193d0bf7
  35. 35
    Hall, G. M.; Woods, G. J.; Patterson, J. L. Br. J. Anaesth. 1984, 56, 903– 904 DOI: 10.1093/bja/56.8.903
    Google Scholar
    35
    Half-life of plasma cholinesterase
    Hall, G. M.; Wood, G. J.; Paterson, J. L.
    British Journal of Anaesthesia (1984), 56 (8), 903-4CODEN: BJANAD; ISSN:0007-0912.
    The half-life of plasma cholinesterase (EC 3.1.1.8) was detd. by measurement of the rate of reappearance of enzyme activity after marked depletion assocd. with repeated plasma exchanges. Half-life values of 5.0 and 5.4 days were found in 2 patients.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL2cXlsVyktr8%253D&md5=342f935c61f747f057735e5591f876aa
  36. 36
    Raveh, L.; Grauer, E.; Grunwald, J.; Cohen, E.; Ashani, Y. Toxicol. Appl. Pharmacol. 1997, 145, 43– 53 DOI: 10.1006/taap.1997.8160
    Google Scholar
    36
    The stoichiometry of protection against soman and VX toxicity in monkeys pretreated with human butyrylcholinesterase
    Raveh, Lily; Grauer, Ettie; Grunwald, Jacob; Cohen, E.; Ashani, Yacov
    Toxicology and Applied Pharmacology (1997), 145 (1), 43-53CODEN: TXAPA9; ISSN:0041-008X. (Academic)
    Bioscavengers of organophosphates (OP) have been examd. as potential substitutes for the currently approved drug treatment against OP toxicity. The present work was designed to assess the ability of butyrylcholinesterase, purified from human serum (HuBChE), to prevent the toxicity induced by soman and VX in rhesus monkeys. The consistency of the data across species was then evaluated as the basis for the extrapolation of the data to humans. The av. mean residence time of the enzyme in the circulation of monkeys following an i.v. loading was 34 h. High bioavailability of HuBChE in blood (>80%) was demonstrated after i.m. injection. A molar ratio of HuBChE:OP ∼1.2 protected against an i.v. bolus injection of 2.1 × LD50 VX, while a ratio of 0.62 was sufficient to protect monkeys against an i.v. dose of 3.3 × LD50 of soman, with no addnl. postexposure therapy. A remarkable protection was also seen against soman-induced behavioral deficits detected in the performance of a spatial discrimination task. The consistency of the results across several species offers a reliable prediction of both the stoichiometry of the scavenging and the extent of prophylaxis with HuBChE against nerve agent toxicity in humans.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXktl2htbg%253D&md5=05dff66162cebdd4cba95a1d51bc6325
  37. 37
    Raveh, L.; Grunwald, J.; Marcus, D.; Papier, Y.; Cohen, E.; Ashani, Y. Biochem. Pharmacol. 1993, 45, 2465– 2474 DOI: 10.1016/0006-2952(93)90228-O
    Google Scholar
    There is no corresponding record for this reference.
  38. 38
    Lenz, D. E.; Maxwell, D. M.; Koplovitz, I.; Clark, C. R.; Capacio, B. R.; Cerasoli, D. M.; Federko, J. M.; Luo, C.; Saxena, A.; Doctor, B. P. Chem.-Biol. Interact. 2005, 157, 205– 210 DOI: 10.1016/j.cbi.2005.10.025
    Google Scholar
    38
    Protection against soman or VX poisoning by human butyrylcholinesterase in guinea pigs and cynomolgus monkeys
    Lenz, David E.; Maxwell, Donald M.; Koplovitz, Irwin; Clark, Connie R.; Capacio, Benjamin R.; Cerasoli, Douglas M.; Federko, James M.; Luo, Chunyuan; Saxena, Ashima; Doctor, Bhupendra P.; Olson, Carl
    Chemico-Biological Interactions (2005), 157-158 (), 205-210CODEN: CBINA8; ISSN:0009-2797. (Elsevier Ireland Ltd.)
    Human butyrylcholinesterase (HuBuChE), purified from outdated human plasma, is being evaluated for efficacy against nerve agents in guinea pigs and cynomolgus monkeys. Previous studies in rodents and nonhuman primates demonstrated that pretreatment of animals with enzymes that can scavenge nerve agents could provide significant protection against behavioral and lethal effects of nerve agent intoxication. In prepn. for evaluation of efficacy of HuBuChE prior to initiating an investigational new drug (IND) application, the pharmacokinetics of HuBuChE were evaluated in guinea pigs and in cynomolgus monkeys. HuBuChE was injected i.m. at two doses, and blood samples were taken to follow the time-course of HuBuChE in blood for up to 168 h after administration. In guinea pigs, the two doses of HuBuChE, 19.9 and 32.5 mg/kg, produced similar times of maximal blood concn. (Tmax of 26.0 and 26.8 h, resp.) and similar elimination half-times (t1/2 of 64.6 and 75.5 h, resp.). Enzyme levels were still 10-fold over baseline at 72 h. Based on these data, guinea pigs were administered 150 mg/kg of enzyme i.m. and challenged at T max. Soman or VX doses were approx. 1.5, 2.0 and 2.0 × LD50 administered s.c. in sequence at 90-120 min apart. None of the animals displayed signs of organophosphorus (OP) anticholinesterase intoxication at any of the challenge levels, and all survived for the 14-day duration of the expt. Similar expts. were carried out with cynomolgus monkeys to det. the pharmacokinetics of HuBuChE and its efficacy against soman. The complete survival of nearly all animals tested to date, coupled with the maximal blood concn. and half-life elimination profile obtained for HuBuChE after i.m. injection, provides strong support for the continued development of HuBuChE as a product to protect against nerve agents.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXhtlShs7jM&md5=ff0b18498b651db8c6357fa3ea9a1c4c
  39. 39
    Black, R.; Clarke, R.; Harrison, J.; Read, R. Xenobiotica 1997, 27, 499– 512 DOI: 10.1080/004982597240460
    Google Scholar
    There is no corresponding record for this reference.
  40. 40
    Nakahara, Y. J. Chromatogr., Biomed. Appl. 1999, 733, 161– 180 DOI: 10.1016/S0378-4347(99)00059-6
    Google Scholar
    40
    Hair analysis for abused and therapeutic drugs
    Nakahara, Y.
    Journal of Chromatography B: Biomedical Sciences and Applications (1999), 733 (1 + 2), 161-180CODEN: JCBBEP; ISSN:0378-4347. (Elsevier Science B.V.)
    A review and discussion with 164 refs. which focuses on basic aspects and recent studies of hair anal. for abused and therapeutic drugs. Firstly, biol. of hair and sampling of hair specimens have been commented for the sake of correct interpretation of the results from hair anal. Then the usual washing methods of hair samples and the extn. methods for drugs in hair have been shown and commented on. Anal. methods for each drug have been discussed by the grouping of three anal. methods, namely immunoassay, HPLC-CE and GC-MS. The outcomes of hair anal. studies have been reviewed by dividing into six groups; morphine and related, cocaine and related, amphetamines, cannabinoids, the other abused drugs and therapeutic drugs. In addn., reports on stability of drugs in the living hair and studies on drug incorporation into hair and dose-hair concn. relationships have been reviewed. Applications of hair anal. to the estn. of drug history, discrimination between OTC drug use and illegal drug use, drug testing for acute poisoning, gestational drug exposure and drug compliance have also been reviewed. Finally, the promising prospects of hair anal. have been described.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1MXmvVKhtLc%253D&md5=81417dd85b3524b7b5a4d64918f521b3
  41. 41
    Hadidi, K. A.; Almasad, J. K.; Al-Nsour, T.; Abu-Ragheib, S. Forensic Sci. Int. 2003, 135, 129– 136 DOI: 10.1016/S0379-0738(03)00196-8
    Google Scholar
    41
    Determination of tramadol in hair using solid phase extraction and GC-MS
    Hadidi, Kamal A.; Almasad, Jamal K.; Al-Nsour, Thair; Abu-Ragheib, Samih
    Forensic Science International (2003), 135 (2), 129-136CODEN: FSINDR; ISSN:0379-0738. (Elsevier Science Ltd.)
    Tramadol is a centrally acting synthetic analgesic with μ-opioid receptor agonist activity, it is a widely prescribed analgesic used in the treatment of moderate to severe pain and as an alternative to opiates. Tramadol causes less respiratory depression than morphine at recommended doses. Its efficacy and low incidence of side effects lead to its unnecessary prescribing in patients with mild pain. Tramadol was classified as a "controlled drug" long after its approval for use in Jordan. Anal. of drugs of abuse in hair has been used in routine forensic toxicol. as an alternative to blood in studying addiction history of drug abusers. A method for the detn. of tramadol in hair using solid phase extn. and gas chromatog.-mass spectrometry (GC-MS) is presented, the method offers excellent precision (3.5-9.8%, (M)=6.77%), accuracy (6.9-12%, M=9.4%) and limit of detection 0.5 ng/mg. The recovery was in the range of 87-94.3% with an av. of 90.75%. The calibration curve was linear over the concn. range 0.5-5.0 ng/mg hair with correlation coeff. of 0.998. The developed method was tested on 11 hair samples taken from patients using tramadol as prescribed by their physician along with other different drugs in treating chronic illnesses. Tramadol was detected in all hair samples at a concn. of 0.176-16.3 ng/mg with mean concn. of 4.41 ng/mg. The developed method has the potential of being applied in forensic drug hair testing. In Jordan, hair drug testing started to draw the attention of legal authorities which stimulated forensic toxicologists in recent years to develop methods of anal. of drugs known or have the potential to be abused.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXmt1ensb8%253D&md5=98eca8ae3a404acc7685a7cb5b5d6c67
  42. 42
    Boumba, V.; Ziavrou, K.; Vougiouklakis, T. Int. J. Toxicol. 2006, 25, 143– 163 DOI: 10.1080/10915810600683028
    Google Scholar
    42
    Hair as a biological indicator of drug use, drug abuse or chronic exposure to environmental toxicants
    Boumba, Vassiliki A.; Ziavrou, Kallirroe S.; Vougiouklakis, Theodore
    International Journal of Toxicology (2006), 25 (3), 143-163CODEN: IJTOFN; ISSN:1091-5818. (Taylor & Francis, Inc.)
    A review. In recent years hair has become a fundamental biol. specimen, alternative to the usual samples blood and urine, for drug testing in the fields of forensic toxicol., clin. toxicol. and clin. chem. Moreover, hair-testing is now extensively used in workplace testing, as well as, on legal cases, historical research etc. This article reviews methodol. and practical issues related to the application of hair as a biol. indicator of drug use/abuse or of chronic exposure to environmental toxicants. Hair structure and the mechanisms of drug incorporation into it are commented. The usual prepn. and extn. methods as well as the anal. techniques of hair samples are presented and commented on. The outcomes of hair anal. have been reviewed for the following categories: drugs of abuse (opiates, cocaine and related, amphetamines, cannabinoids), benzodiazepines, prescribed drugs, pesticides and org. pollutants, doping agents and other drugs or substances. Finally, the specific purpose of the hair testing is discussed along with the interpretation of hair anal. results regarding the limitations of the applied procedures.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD28XntFelsro%253D&md5=003f69589b4497e8e0a8709daffe04b8
  43. 43
    Moore, C.; Guzaldo, F.; Donahue, T. J. Anal. Toxicol. 2001, 25, 555– 558 DOI: 10.1093/jat/25.7.555
    Google Scholar
    43
    The determination of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in hair using negative ion gas chromatography-mass spectrometry and high-volume injection
    Moore, Christine; Guzaldo, Frank; Donahue, Thomas
    Journal of Analytical Toxicology (2001), 25 (7), 555-558CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
    The detn. of 11-nor-Δ9-THC-9-carboxylic acid (THC-COOH) in hair specimens at the sensitivity required to detect marijuana users is a difficult anal. problem. A sensitive and specific method has been developed for the quant. assay of THC-COOH in hair. Hair specimens were washed, incubated in sodium hydroxide, subjected to solid-phase extn., and analyzed using high-vol. injection coupled with neg. chem. ionization (NCI) mass spectrometry. A common disadvantage of chem. ionization, the prodn. of a single mass-to-charge ratio ion, was also addressed. By specific selection of the derivatizing agent, three ions were monitored, allowing the calcn. of two ion ratios, as in electron impact mode. The method was applied to several hair specimens taken from known marijuana users and workplace specimens. This is the first publication describing the use of high-vol. injection and NCI mass spectrometry for the detn. of THC-COOH in hair. (c) 2001 Preston Publications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3MXnsVCgsr8%253D&md5=3b992d265d933780449033eae93d7bfc
  44. 44
    Phinney, K. W.; Sander, L. C. Anal. Bioanal. Chem. 2004, 378, 144– 149 DOI: 10.1007/s00216-003-2366-3
    Google Scholar
    44
    Liquid chromatographic method for the determination of enantiomeric composition of amphetamine and methamphetamine in hair samples
    Phinney, Karen W.; Sander, Lane C.
    Analytical and Bioanalytical Chemistry (2004), 378 (1), 144-149CODEN: ABCNBP; ISSN:1618-2642. (Springer-Verlag)
    Interest in hair anal. as an alternative or complementary approach to urinalysis for drug abuse detection has grown in recent years. Hair anal. can be particularly advantageous for drugs such as amphetamine and methamphetamine that are rapidly excreted. Confirmation of abuse of these stimulants is complicated by the fact that some forms are found in legitimate medications. Examn. of the enantiomeric compn. of amphetamine and methamphetamine in hair samples can provide valuable assistance in interpreting drug testing results. The authors developed a liq. chromatog. for the sepn. of amphetamine and methamphetamine enantiomers isolated from human hair samples. The drug enantiomers were sepd. on a chiral stationary phase after derivatization with an achiral fluorescent agent. The methodol. was evaluated with a Std. Ref. that contained several drugs of abuse including amphetamine and methamphetamine.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXps1yjtbk%253D&md5=1d2f82f49de102b6b7fd2c5fb16da156
  45. 45
    Romolo, F. S.; Rotolo, M. C.; Palmi, I.; Pacifici, R.; Lopez, A. Forensic Sci. Int. 2003, 138, 17– 26 DOI: 10.1016/j.forsciint.2003.07.013
    Google Scholar
    45
    Optimized conditions for simultaneous determination of opiates, cocaine and benzoylecgonine in hair samples by GC-MS
    Romolo, F. S.; Rotolo, M. C.; Palmi, I.; Pacifici, R.; Lopez, A.
    Forensic Science International (2003), 138 (1-3), 17-26CODEN: FSINDR; ISSN:0379-0738. (Elsevier Science Ltd.)
    The present paper describes a qual. and quant. method for the simultaneous detection of opiates, cocaine and benzoylecgonine from human hair samples. Every step of the anal. procedure was studied to find the optimized conditions. Nine different incubation systems were examd. The influence of different pH values of samples on the isolation of analytes from the incubation media by Bond Elut cartridges and the stability of the compds. of interest in the different incubation media and conditions were investigated. The extg. power of different incubation media was studied as well. The phosphate buffer 0.1N at pH 5 was chosen as the extn. medium in an optimized procedure for simultaneous detn. of opiates, cocaine and benzoylecgonine in hair samples. The method developed was validated. Recoveries were 90% for morphine (M), 81% for 6-monoacetylmorphine (6-AM), 90% for codeine (CD), 86% for cocaine (C) and 90% for benzoylecgonine (BE). Relative std. deviation for inter-day precision was better than 12%. The limits of detection resulted as 0.05 ng/mg for M and C, as 0.08 for 6-AM and as 0.2 ng/mg for BE. Forty hair samples collected from drug abusers admitted to centers for detoxification treatment were analyzed obtaining 23 pos. results for opiates and/or cocaine. Twelve hair specimens longer than 10 cm were analyzed following a sectional approach. In the six pos. cases, it was interesting to find that the 6-AM/M ratio generally decreased for each sample from the proximal segment to the distal segments. Moreover, the 6-AM/M ratio was generally lower than 1 in the intermediate and distal segments.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXpt1WitL4%253D&md5=562c0571386f6de1d8d2a5015636d777
  46. 46
    Scheidweiler, K. B.; Huestis, M. A. Anal. Chem. 2004, 76, 4358– 4363 DOI: 10.1021/ac049555t
    Google Scholar
    There is no corresponding record for this reference.
  47. 47
    Brewer, W. E.; Galipo, R. C.; Sellers, K. W.; Morgan, S. L. Anal. Chem. 2001, 73, 2371– 2376 DOI: 10.1021/ac000871r
    Google Scholar
    There is no corresponding record for this reference.
  48. 48
    Wada, M.; Nakashima, K. Anal. Bioanal. Chem. 2006, 385, 413– 415 DOI: 10.1007/s00216-006-0332-6
    Google Scholar
    48
    Hair analysis: an excellent tool for confirmation of drug abuse
    Wada, Mitsuhiro; Nakashima, Kenichiro
    Analytical and Bioanalytical Chemistry (2006), 385 (3), 413-415CODEN: ABCNBP; ISSN:1618-2642. (Springer)
    A review of methods for hair anal. forensic toxicol. and drug abuse studies.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD28XkvVWlt7o%253D&md5=6bebaf84f67a9cf2a400d95fe1d66523
  49. 49
    Kintz, P.; Cirimele, V.; Jamey, C.; Ludes, B. J. Forensic Sci. 2003, 48, 195– 200 DOI: 10.1520/JFS2002209
    Google Scholar
    49
    Testing for GHB in hair by GC/MS/MS after a single exposure. Application to document sexual assault
    Kintz, Pascal; Cirimele, Vincent; Jamey, Carole; Ludes, Bertrand
    Journal of Forensic Sciences (2003), 48 (1), 195-200CODEN: JFSCAS; ISSN:0022-1198. (American Society for Testing and Materials)
    Gamma-hydroxybutyric acid, or GHB, is a substance naturally present within mammal species. Properties of neurotransmitter or neuromodulator are generally given to this substance. GHB is therapeutically used as an anesthetic, but can be used for criminal offenses (date-rape drug). It appears that the window of detection of GHB is very short in both blood and urine, and therefore its presence is very difficult to prove after a rape case. In order to document single exposure, we investigated the use of hair. Hair was collected one month after the allegated event in order to sample the corresponding period after regular growing. After rapid (2 min) decontamination with dichloromethane, the hair shaft was cut into 3-mm segments. They were overnight incubated in 0.01 N NaOH in the presence of GHB-d6, followed by neutralization and extn. in Et acetate under acidic conditions. GHB (precursor ion m/z 233, productions m/z 147 and 148) was tested by GC/MS/MS (Finnigan TSQ 700) after derivatization with BSTFA + 1% TMCS. Physiol. concns. (n = 24) were in the range 0.5 to 12.0 ng/mg, with no influence due to hair color. No variation of concns. was obsd. along the hair shaft in controlled subjects, except for the proximal segment, due to an incorporation through sweat. This demonstrates that endogenous levels for each single subject are const. during hair growth. A controlled human administration of 25 mg/kg to a volunteer demonstrated that a single exposure to GHB is detectable in hair after segmentation. In a case of rape under influence, a clear increase of the corresponding segment (about 2.4 ng/mg) in time was obsd., in comparison with the other segments (0.6 to 0.8 ng/mg). This study demonstrates that a single exposure to GHB in a case of sexual assault can be documented by hair anal. when collected about one month after the crime.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXhtVSntL8%253D&md5=be588da0f61623cdee2947f9fe6c4db8
  50. 50
    Negrusz, A.; Moore, C. M.; Hinkel, K. B.; Stockham, T. L.; Verma, M.; Strong, M. J.; Janicak, P. G. J. Forensic Sci. 2001, 46, 1143– 1151 DOI: 10.1520/JFS15113J
    Google Scholar
    50
    Deposition of 7-aminoflunitrazepam and flunitrazepam in hair after a single dose of Rohypnol
    Negrusz, Adam; Moore, Christine M.; Hinkel, Karley B.; Stockham, Teri L.; Verma, Mauli; Strong, Mary Jane; Janicak, Philip G.
    Journal of Forensic Sciences (2001), 46 (5), 1143-1151CODEN: JFSCAS; ISSN:0022-1198. (American Society for Testing and Materials)
    In recent years, there has been a notable increase in the no. of reports on drug-facilitated sexual assault. Benzodiazepines are the most common so-called "date-rape" drugs, with flunitrazepam (Rohypnol) being one of the most frequently mentioned. The aim of this study was to det. whether flunitrazepam and its major metabolite 7-aminoflunitrazepam could be detected in hair collected from ten healthy volunteers after receiving a single 2 mg dose of Rohypnol using solid phase extn. and NCI-GC-MS. Such data would be of great importance to law enforcement agencies trying to det. the best time interval for hair collection from a victim of drug-facilitated sexual assault in order to reveal drug use. Ten healthy volunteers (eight women and two men, 21 to 49 yr old) participated in the study. The following hair samples were collected from each volunteer: one before flunitrazepam administration, and 1, 3, 5, 14, 21, and 28 days after. In five volunteers, 7-aminoflunitrazepam was detected 24 h after flunitrazepam administration and remained in hair throughout the entire 28-day study period (0.6-8.0 pg/mg). In two cases, 7-aminoflunitrazepam appeared in hair 21 days after drug intake (0.5-2.7 pg/mg), and in two subjects 14 days later (0.5-5.4 pg/mg). In one volunteer, 7-aminoflunitrazepam was detected on day 14 and 21 but concns. were below the quantitation limit. Flunitrazepam was detected in some samples but all concns. were below the quantitation limit (0.5-2.3 pg/mg).
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3MXntFGksL8%253D&md5=b70004c248b45a54db8cdf5b5f8ae41a
  51. 51
    Goulle, J. P.; Cheze, M.; Pepin, G. J. Anal. Toxicol. 2003, 27, 574– 580 DOI: 10.1093/jat/27.8.574
    Google Scholar
    51
    Determination of Endogenous Levels of GHB in Human Hair. Are there Possibilities for the Identification of GHB Administration through Hair Analysis in Cases of Drug-Facilitated Sexual Assault?
    Goulle, Jean Pierre; Cheze, Marjorie; Pepin, Gilbert
    Journal of Analytical Toxicology (2003), 27 (8), 574-580CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
    The authors have developed a GC-MS-MS assay for GHB in human hair. 5 Mg of washed hair were hydrolyzed by 1M or 0.01M NaOH before a liq.-liq. extn. with Et acetate under acidic conditions. GHB-d6 was used as the internal std. TMS derivs. were formed before injection. TBDMS derivs. were used in cases of strong chromatog. interferences or in a confirmatory procedure. Anal. of basal levels of GHB in 61 drug-free donors gave the following results: the mean measured concn. for blond hair was 0.60 ng/mg (n = 12), SD = 0.19 ng/mg, and extreme figures were in the range 0.35-0.95 ng/mg. For brown hair, the mean measured concn. was 0.90 ng/mg (n = 30), SD = 0.42 ng/mg, and extreme figures 0.41-1.86 ng/mg. For black hair, the mean measured concn. was 0.90 ng/mg (n = 19), SD = 0.37 ng/mg, and extreme figures 0.32-1.54 ng/mg, showing no significant differences depending on hair color. Anal. of basal levels of GHB of 12 or more specimens in segmented hair showed a mean concn. of 1.22 ng/mg (0.31-8.4 ng/mg) and a relative std. deviation for each individual ranging from 6.75% to 37.98%. GHB was administered to a healthy 53-yr-old white male (light brown hair) at oral dosages of 30, 45, and 60 mg/kg. Beard hair was collected just before administration and 24 h after (and each day for one week for the last dose), and a 7.5-cm scalp hair lock was collected 7 days after the last dose. A rise in GHB concn. was obsd. in beard hair for the 45 and 60 mg/kg dosages with a max. at 24 h, whereas no change was obsd. for the 30 mg/kg dosage. Scalp hair was segmented into 3-mm long segments. The 3 proximal last segments showed significantly (0.0005 < p < 0.005) different concns. of GHB (1.22, 1.27, and 1.66 ng/mg, resp.) when compared with the basal physiol. level of GHB in this same person (mean = 0.62 ng/mg, SD = 0.15 ng/mg). A case of daily GHB abuse during bodybuilding allowed us to det. a concn. of GHB of 14 ng/mg, in a 2-cm long segment (black hair). A case of rape under the influence of GHB was documented through hair anal. (black hair) and pos. anal. of the glass she used. Sampled 7 days after the sexual assault, the 3 last 3-mm long proximal segments tested for GHB exhibited concns. of 3.1-5.3 and 4.3 ng/mg, resp., whereas the mean physiol. level detd. in this woman was 0.71 ng/mg, SD = 0.17 ng/mg. The authors advise a 2 -step hair sampling as evidence of GHB consumption: the 1st sample at the time of exposure to show the contamination by sweat of the proximal segment in case of recent administration with a significant rise of hair level at the root, and the second after at least 3 or 4 wk to avoid this contamination and det. the levels incorporated in the hair matrix before, during, and after the exposure. (c) 2003 Preston Publications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXoslOju70%253D&md5=bc63502f405ebc734b70e82bf31aa44a
  52. 52
    Frison, G.; Favretto, D.; Tedeschi, L.; Ferrara, S. D. Forensic Sci. Int. 2003, 133, 171– 174 DOI: 10.1016/S0379-0738(03)00064-1
    Google Scholar
    52
    Detection of thiopental and pentobarbital in head and pubic hair in a case of drug-facilitated sexual assault
    Frison, Giampietro; Favretto, Donata; Tedeschi, Luciano; Ferrara, Santo Davide
    Forensic Science International (2003), 133 (1-2), 171-174CODEN: FSINDR; ISSN:0379-0738. (Elsevier Science Ireland Ltd.)
    The quali-quant. detn. of 2 barbiturates, thiopental and its metabolite pentobarbital, in head and pubic hair samples of a woman who had been sexually assaulted during hospitalization, is reported. Hair was analyzed by means of solid-phase microextn. (SPME) and gas chromatog.-multiple mass spectrometry (GC-MS-MS), in chem.-ionization conditions. Thiopental and pentobarbital were found in 3 proximal head hair segments (sample 1A: 0.30 and 0.40 ng/mg; sample 1B: 0.20 and 0.20 ng/mg; sample 3: 0.15 and 0.20 ng/mg) and pubic hair sample. Two distal head hair segments were neg. for both barbiturates. Despite the lack of collection and toxicol. anal. of blood or urine samples within the hospital setting, anal. findings from hair revealed the use of the anesthetic agent thiopental to sedate the victim quickly and deeply and commit sexual assault.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXjs1aiu78%253D&md5=f10b965ff10eebc034920c162fe28c02
  53. 53
    Negrusz, A.; Moore, C. M.; Kern, J. L.; Janicak, P. G.; Strong, M. J.; Levy, N. A. J. Anal. Toxicol. 2000, 24, 614– 620 DOI: 10.1093/jat/24.7.614
    Google Scholar
    53
    Quantitation of clonazepam and its major metabolite 7-aminoclonazepam in hair
    Negrusz, Adam; Moore, Christine M.; Kern, Jennifer L.; Janicak, Philip G.; Strong, Mary Jane; Levy, Naomi A.
    Journal of Analytical Toxicology (2000), 24 (7), 614-620CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
    As with some other benzodiazepines, clonazepam (CLO) is a drug possibly used in "date-rape" situations. A method using solid-phase extn. followed by a highly sensitive neg. chem. ionization gas chromatog.-mass spectrometry procedure was developed for the simultaneous quantitation of CLO and its major metabolite, 7-aminoclonazepam (7-ACLO), in hair. The method has potential application to alleged drug-facilitated rape cases. To det. the feasibility of detecting 7-ACLO and CLO in hair, specimens were collected from psychiatric patients treated with CLO, divided into 2-cm segments, and analyzed. Std. curves for 7-ACLO (1-1000 pg/mg) and CLO (10-400 pg/mg) had correlation coeffs. of 0.998. All precision and accuracy values were within acceptable limits. 7-ACLO was present in measurable quantities (1.37-1267 pg/mg) in 9 of 10 patient samples. CLO concns. in hair were much lower (10.7-180 pg/mg). In 4 of 10 cases, CLO was not detected in hair. Two patients who had never before been treated with CLO received a single 2-mg dose of the drug. Approx. 3 wk later, hair samples were collected, and measurable quantities of 7-ACLO (4.8 pg/mg) were detected in the 1st segment (proximal) of one of those samples, and traces of the drug were present in the other sample. It is concluded that 7-ACLO is deposited in hair in much higher quantities than the parent drug and remains there for extended periods of time. The study also indicates that it is possible to detect 7-ACLO after a single dose of CLO, as in the typical date-rape scenarios. (c) 2000 Preston Publications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3cXntlOltr4%253D&md5=6a4b6131af7874534652eb1cac027253
  54. 54
    Covaci, A.; Tutudaki, M.; Tsatsakis, A. M.; Schepens, P. Chemosphere 2002, 46, 413– 418 DOI: 10.1016/S0045-6535(01)00065-0
    Google Scholar
    There is no corresponding record for this reference.
  55. 55
    Zhang, H.; Chai, Z.; Sun, H. Environ. Int. 2007, 33, 685– 693 DOI: 10.1016/j.envint.2007.02.003
    Google Scholar
    There is no corresponding record for this reference.
  56. 56
    Margariti, M. G.; Tsatsakis, A. M. Biomarkers 2009, 14, 137– 147 DOI: 10.1080/13547500902792912
    Google Scholar
    There is no corresponding record for this reference.
  57. 57
    Tsatsakis, A. M.; Tutudaki, M.; Tzatzarakis, M. N.; Dawson, A.; Mohamed, F.; Christaki, M.; Alegakis, A. K. Hum. Exp. Toxicol. 2012, 31, 266– 273 DOI: 10.1177/0960327111403171
    Google Scholar
    57
    Is hair analysis for dialkyl phosphate metabolites a suitable biomarker for assessing past acute exposure to organophosphate pesticides?
    Tsatsakis, A. M.; Tutudaki, M.; Tzatzarakis, M. N.; Dawson, A.; Mohamed, F.; Christaki, M.; Alegakis, A. K.
    Human & Experimental Toxicology (2012), 31 (3), 266-273CODEN: HETOEA; ISSN:0960-3271. (Sage Publications Ltd.)
    In the present paper, the possibility to use dialkyl phosphate metabolites (DAPs) hair segmental anal. as a biomarker of past acute exposure to organophosphates is examd. Hair samples of four acute poisoning survivors were collected and segmental hair anal. was performed. The total hair samples were divided to 1 cm segments and analyzed by gas chromatog.-mass spectrometry (GC-MS) for the presence of four DAP metabolites, di-Me phosphate (DMP), di-Et phosphate (DEP), di-Et thiophosphate (DETP) and di-Et dithiophosphate (DEDTP). Results were examd. under the light of pesticide type and time of hair sample collection. Although DAPs were detected all along the hair shaft, higher concns. (peaks) were detected in the segments proximate to the suicide period. It was also obsd. that the elevated concns. of the present metabolites corresponded to the ones produced by the ingested parent compd. Conclusively, measurements of DAPs in the appropriate hair segments of OP-poisoned patients can be used for assessing past acute exposure to organophosphates in certain cases.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xot1ygu74%253D&md5=a0587da5a4980c50f741e4ba9c83160f
  58. 58
    Tsatsakis, A. M.; Tzatzarakis, M. N.; Tutudaki, M.; Babatsikou, F.; Alegakis, A. K.; Koutis, C. Hum. Exp. Toxicol. 2008, 27, 933– 940 DOI: 10.1177/0960327108102047
    Google Scholar
    58
    Assessment of levels of organochlorine pesticides and their metabolites in the hair of a Greek rural human population
    Tsatsakis, A. M.; Tzatzarakis, M. N.; Tutudaki, M.; Babatsikou, F.; Alegakis, A. K.; Koutis, C.
    Human & Experimental Toxicology (2008), 27 (12), 933-940CODEN: HETOEA; ISSN:0960-3271. (Sage Publications Ltd.)
    We present the assessment of chronic exposure of the rural population of Helia Peloponnesus, Greece to banned organochlorine pesticides, hexachlorocyclohexane (HCH), and 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT), using hair anal. A total of 222 head hair samples were collected and analyzed for the presence of those organochlorine pesticides and their metabolites or isomers. Gas chromatog. coupled to mass spectrometry was used to measure the levels of the pollutants. The median concns. of α-HCH, hexachlorobenzene, lindane, ortho para 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (opDDE), para para 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (ppDDE), ortho para 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (opDDD), para para 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (ppDDD) + ortho para 1,1,1-trichloro-2,2-bis(4-chlorophenyl)-ethane, and para para 1,1,1-trichloro-2,2-bis(4-chloro-phenyl)-ethane were detd. at 40.4, 19.7, 124.2, 6.2, 7.8, 73.1, 8.0, and 5.7 pg/mg. The median concn. of total HCHs and DDTs were 117.8 pg/mg and 9.4 pg/mg, resp. The levels of total HCHs were much higher than the levels of DDTs in the hair samples of the studied population. This may be attributed to the presence of lindane, a pesticide officially banned in 2002. It is interesting to see that DDTs are still traced in samples despite their use being banned for more than three decades. There was no difference in the levels of the detected pesticides in hair sampled from men or women. The concn. of HCHs remains high and relatively stable across the age groups, suggesting const. exposure until very recently. The concn. of the total DDTs and the parent compd., pp-DDT presents a statistically significant decreasing trend across the age groups.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXltVOgsbg%253D&md5=2d427cbc71019db9810fc22ae7be3e5a
  59. 59
    Smith-Baker, C.; Saleh, M. A. J. Environ. Sci. Health, Part B 2011, 46, 648– 653 DOI: 10.1080/03601234.2012.597701
    Google Scholar
    There is no corresponding record for this reference.
  60. 60
    Tsatsakis, A. M.; Tutudaki, M. I.; Tzatzarakis, M. N.; Psaroudakis, K.; Dolapsakis, G. P.; Michalodimitrakis, M. N. Vet. Hum. Toxicol. 1998, 40, 200– 203
    Google Scholar
    60
    Pesticide deposition in hair: preliminary results of a model study of methomyl incorporation into rabbit hair
    Tsatsakis, A. M.; Tutudaki, M. I.; Tzatzarakis, M. N.; Psaroudakis, K.; Dolapsakis, G. P.; Michalodimitrakis, M. N.
    Veterinary and Human Toxicology (1998), 40 (4), 200-203CODEN: VHTODE; ISSN:0145-6296. (Comparative Toxicology Laboratories, Kansas State University)
    This work studied the incorporation of methomyl, a carbamate insecticide, into the hair of New Zealand white rabbits. A total of 600 mg methomyl was administered by drinking water over 4 mo, and acetyl-cholinesterase activity in serum was monitored. At the end of the dosing period, hair from the back of the rabbits was cut off, and the methomyl concn. was measured using ELISA and HPLC. A decrease of serum acetylcholinesterase occurred. The top cm of hair contained no methomyl, the second cm contained 0.9 ng/mg and the 3rd cm of hair contained 3 ng methomyl/mg. Methomyl was incorporated into the rabbit hair in a process independent of gender but dependent on the hair growth rate.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXltFSmsbo%253D&md5=936cc70a42ebcb08294407d1f388276a
  61. 61
    Tutudaki, M.; Tsakalof, A. K.; Tsatsakis, A. M. Hum. Exp. Toxicol. 2003, 22, 159– 164 DOI: 10.1191/0960327103ht334oa
    Google Scholar
    61
    Hair analysis used to assess chronic exposure to the organophosphate diazinon: A model study with rabbits
    Tutudaki, Maria; Tsakalof, Andreas K.; Tsatsakis, Aristidis M.
    Human & Experimental Toxicology (2003), 22 (3), 159-164CODEN: HETOEA; ISSN:0960-3271. (Arnold, Hodder Headline)
    The main purpose of the present study was to det. whether hair anal. would be a suitable method to assess chronic exposure of rabbits to the pesticide diazinon. A controlled study was designed, in which white rabbits of the New Zealand variety were systemically exposed to two dosage levels (15 mg/kg per day and 8 mg/kg per day) of the pesticide, through their drinking water, for a period of 4 mo. Hair samples from the back of the rabbits were removed before commencing the expt. and at the end of the dosing period. Parallel expts. with spiked hair were carried out in order to design a simple and efficient method of extn. of diazinon from hair. The hair was pulverized in a ball mill homogenizer, incubated in methanol at 37°C overnight, liq.-liq. extd. with Et acetate and measured by chromatog. techniques (GC-NPD and GC-MS) for confirmation. The concn. of the diazinon in the hair of the exposed animals ranged from 0.11 to 0.26 ng/mg hair. It was concluded that there is a relationship between the administered dose and the detected pesticide concn. in hair. Finally, it seems that hair anal. may be used to investigate chronic exposure to the pesticide.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXjslCru7g%253D&md5=622e25095a2c2b6a19abebd9bacfd8ed
  62. 62
    Tutudaki, M.; Tsatsakis, A. M. J. Anal. Toxicol. 2005, 29, 805– 809 DOI: 10.1093/jat/29.8.805
    Google Scholar
    62
    Pesticide Hair Analysis: Development of a GC-NCI-MS Method to Assess Chronic Exposure to Diazinon in Rats
    Tutudaki, Maria; Tsatsakis, Aristidis M.
    Journal of Analytical Toxicology (2005), 29 (8), 805-809CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
    The present study aimed to improve the gas chromatog.-mass spectrometry (GC-MS) method, already developed in our lab., for trace anal. of diazinon in hair. Furthermore, it aimed to compare the disposition of the pesticide in the hair of 2 different animal species, one susceptible to diazinon toxicity and one resistant, under identical exptl. conditions. Sprague Dawley rats were systemically exposed to 2 dose levels (6 mg/kg/day and 3 mg/kg/day) of the pesticide, through their drinking water, for a period of one and a half months. Hair samples from the back of the rats were removed before commencing the expt. and at the end of the dosing period. Diazinon was selectively isolated from pulverized hair, sample or spiked, by stepwise consequent extns. with methanol and Et acetate and quantified by GC-neg. chem. ionization-MS. It was found that the concn. of diazinon in the hair of exposed animals was dose dependent and was found to be 0.24 ± 0.01 ng/mg (n = 5) and 0.53 ± 0.05 ng/mg (n = 5) for the low and high dosage, resp. The concn. in both dose groups was much higher than the corresponding rabbit hair (rabbits were exposed to the pesticide under similar exptl. conditions) as previously reported. These results strongly point to the possibility of using hair anal. for low-level exposure monitoring of diazinon. (c) 2005 Preston Publications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXht1CqsLnI&md5=2c49bd68e7747008c122a6e1462c373f
  63. 63
    Shih, M.; Smith, J.; McMonagle, J.; Dolzine, T.; Gresham, V. Biol. Mass Spectrom. 1991, 20, 717– 723 DOI: 10.1002/bms.1200201111
    Google Scholar
    63
    Detection of metabolites of toxic alkyl methylphosphonates in biological samples
    Shih, M. L.; Smith, J. R.; McMonagle, J. D.; Dolzine, T. W.; Gresham, V. C.
    Biological Mass Spectrometry (1991), 20 (11), 717-23CODEN: BIMSEH; ISSN:1052-9306.
    The major metabolites and breakdown products of some toxic organophosphonates are their resp. alkyl methylphosphonic acids. These acids ionize at physiol. pH and are not amenable to gas chromatog. anal. in their underivatized forms. Their detection in biol. samples has been difficult because of their presence at only trace levels. Existing anal. methods were developed mainly for measuring these phosphonic acids in environmental samples and at higher concns. In this study, a gas chromatog./mass spectrometric method was devised to provide confirmation and quantification of the organophosphonic acids of soman (GD), sarin (GB) and GF in blood and urine. This report describes the various derivatization conditions that we have studied and demonstrates the characteristic mass spectra by different ionization techniques.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK38Xhs1Onsw%253D%253D&md5=ce52adead6ff23189c60960171b1b93b
  64. 64
    Jakubowski, E.; Heykamp, L.; Durst, H.; Thomson, S. Anal. Lett. 2001, 34, 727– 737 DOI: 10.1081/AL-100103215
    Google Scholar
    64
    Preliminary studies in the formation of ethyl methylphosphonofluoridate from rat and human serum exposed to VX and treated with fluoride ion
    Jakubowski, E. M.; Heykamp, L. S.; Durst, H. D.; Thomson, S. A.
    Analytical Letters (2001), 34 (5), 727-737CODEN: ANALBP; ISSN:0003-2719. (Marcel Dekker, Inc.)
    A method has been developed for the anal. of a VX nerve agent biomarker in blood that is very sensitive, selective and within the capabilities of modern field mobile labs. A VX biomarker was found in spiked human and rat sera after treatment with fluoride ion and acetate buffer. VX was detected by the generation of its corresponding G-series deriv., Et methylphosphonofluoridate (VX-G). This method utilizes a C18 solid-phase extn. (SPE) followed by quantification using a gas chromatograph with either a flame photometric detector (GC-FPD) or a mass spectrometer (GC-MS). Samples are concd. by injecting 40-400 μL of ext. on a Tenax-TA sorbent tube along with 100 pg of decadeuterated di-Et Et phosphonate as the internal std. followed by thermal desorption GC-FPD anal. and GC-MS confirmation. VX-G was completely resolved from sarin (GB) and the method has the potential to resolve other nerve agents in the VX series of cholinesterase inhibitors. The method detection limit was 10.5 pg of agent on column. Quality control samples were analyzed and yielded spike recoveries greater than 95%.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3MXksVOitb0%253D&md5=c184165c9472a3114e6f7311632fbd1c
  65. 65
    Guide for the Care and Use of Laboratory Animals, 8th ed.; National Academies Press: Washington, DC, 2011.
    Google Scholar
    There is no corresponding record for this reference.
  66. 66
    Kalakuntla, R. R.; Kumar, K. S. J. Pharm. Sci. Res. 2009, 3, 1– 10
    Google Scholar
    There is no corresponding record for this reference.
  67. 67
    Loconto, P. R. Trace Environmental Quantitative Analysis Principles, Technique, and Application; CRC Press: Boca Raton, FL, 2006.
    Google Scholar
    There is no corresponding record for this reference.
  68. 68
    Wang, Q.; Xie, J.; Gu, M.; Feng, J.; Ruan, J. Chromatographia 2005, 62, 167– 173 DOI: 10.1365/s10337-005-0600-1
    Google Scholar
    There is no corresponding record for this reference.
  69. 69
    Hayes, T.; Kenny, D.; Hernon-Kenny, L. J. Med. Chem. Def. 2004, 2, 1– 23
    Google Scholar
    There is no corresponding record for this reference.
  70. 70
    Katagi, M.; Nishikawa, M.; Tatsuno, M.; Tsuchiahashi, H. J. Chromatogr., Biomed. Appl. 1997, 698, 81– 88 DOI: 10.1016/S0378-4347(97)00284-3
    Google Scholar
    70
    Determination of the main hydrolysis products of organophosphorus nerve agents, methylphosphonic acids, in human serum by indirect photometric detection ion chromatography
    Katagi, M.; Nishikawa, M.; Tatsuno, M.; Tsuchihashi, H.
    Journal of Chromatography B: Biomedical Sciences and Applications (1997), 698 (1 + 2), 81-88CODEN: JCBBEP; ISSN:0378-4347. (Elsevier)
    For the verification of the use of chem. warfare agents (CWA), sarin, soman and VX, a simple rapid and accurate method which allows us to simultaneously det. their degrdn. products, iso-Pr methylphosphonic acid (IPMPA), pinacolyl methylphosphonic acid (PMPA), Et methylphosphonic acid (EMPA) and methylphosphonic acid (MPA), in human serum, was explored by indirect photometric detection ion chromatog. (IPD-IC) which employs an anion-exchange column. IC anal. was performed after sample prepn. with an Ag+-form cation-exchange resin cartridge, and the four methylphosphonic acids could be sepd. well. The proposed conditions are as follows: eluent, 0.5 mM phthalic acid-0.1 mM Tris (hydroxymethyl) aminomethane-5% acetonitrile; flow-rate, 1.0 mL/min; temp., 50°; UV detector, 266 nm. All four methylphosphonic acids were eluted within 30 min with hardly any disturbance by impurities in the serum. Linear calibration curves were obtained for MPA, EMPA and IPMPA in the concn. range from 50 ng/mL to 1 μg/mL and for PMPA from 100 ng/mL to 1 μg/mL. The relative std. deviation for the methylphosphonic acids ranged from 3.8 to 6.9% at 500 ng/mL and the detection limits were 40 ng/mL for MPA, EMPA and IPMPA and 80 ng/mL for PMPA. The method would be suitable for anal. of human serum samples.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXlslemtr4%253D&md5=ceee5ba8cd1db960546d8e7705c7b32e

Cited By

Click to copy section linkSection link copied!
Citation Statements
Explore this article's citation statements on scite.ai
powered by  Scite

This article is cited by 11 publications.

  1. Nurgul K Bakirhan, Mohamed Brahmi, Miyase Gözde Gündüz, S Irem Kaya, Sermet Sezigen, Sibel A Ozkan. Experimental and computational perspectives on the interaction of nerve agent VX metabolite ethyl methylphosphonic acid with human serum albumin. Microchemical Journal 2024, 205 , 111406. https://doi.org/10.1016/j.microc.2024.111406
  2. Xing-Xing Zong, Niannian Cao, Qian Jing, Xuejun Chen, Tong Shi, Ruihua Zhang, Jingjing Shi, Chen Wang, Liqin Li. Toxic effects and bioaccumulation of pinacolyl methylphosphonate acid in zebrafish following soman exposure to a water environment. RSC Advances 2023, 13 (17) , 11241-11248. https://doi.org/10.1039/D3RA00856H
  3. Ntsoaki Mphuthi, Abongile Jijana, Nikiwe Mhlanga, Munkombwe Muchindu, Sanele Nyembe, Bonex Mwakikunga, Gebhu Ndlovu, Lucky Sikhwivhilu. Chemical warfare agents: an outlook on past and present technologies. 2023, 3-31. https://doi.org/10.1016/B978-0-323-90553-4.00014-7
  4. Jianfeng Wu, Yingjie Zhu, Yulong Liu, Jia Chen, Lei Guo, Jianwei Xie. A novel approach for on-site screening of organophosphorus nerve agents based on DTNB modified AgNPs using surface-enhanced Raman spectrometry. Analytical Methods 2022, 14 (43) , 4292-4299. https://doi.org/10.1039/D2AY01307J
  5. Khirreddine Bouchouareb, Audrey Combès, Valérie Pichon. Determination of nerve agent biomarkers in human urine by a natural hydrophobic deep eutectic solvent-parallel artificial liquid membrane extraction technique. Talanta 2022, 249 , 123704. https://doi.org/10.1016/j.talanta.2022.123704
  6. Khirreddine Bouchouareb, Audrey Combes, Valérie Pichon. Parallel artificial liquid membrane extraction of organophosphorus nerve agent degradation products from environmental samples. Analytica Chimica Acta 2022, 1190 , 339261. https://doi.org/10.1016/j.aca.2021.339261
  7. Katie M Rubin, Bruce A Goldberger, Timothy J Garrett. Detection of Chemical Weapon Nerve Agents in Bone by Liquid Chromatography–Mass Spectrometry. Journal of Analytical Toxicology 2020, 44 (4) , 391-401. https://doi.org/10.1093/jat/bkz118
  8. Jonathan Oyler, Kathleen Maistros, Benjamin Oyler, David Kilgour. Liquid Chromatography–Mass Spectrometry in Analysis of Chemicals Related to the Chemical Weapons Convention. 2020, 1-50. https://doi.org/10.1002/9780470027318.a0408.pub3
  9. Brian A. Logue, Erica Manandhar. Percent residual accuracy for quantifying goodness-of-fit of linear calibration curves. Talanta 2018, 189 , 527-533. https://doi.org/10.1016/j.talanta.2018.07.046
  10. Derese Getnet, Aarti Gautam, Raina Kumar, Allison Hoke, Amrita K. Cheema, Franco Rossetti, Caroline R. Schultz, Rasha Hammamieh, Lucille A. Lumley, Marti Jett, . Poisoning with Soman, an Organophosphorus Nerve Agent, Alters Fecal Bacterial Biota and Urine Metabolites: a Case for Novel Signatures for Asymptomatic Nerve Agent Exposure. Applied and Environmental Microbiology 2018, 84 (21) https://doi.org/10.1128/AEM.00978-18
  11. Aarti Gautam, Derese Getnet, Raina Kumar, Allison Hoke, Amrita K Cheema, Franco Rossetti, Caroline R Schultz, Rasha Hammamieh, Lucille A Lumley, Marti Jett. Altered Fecal Microbiota and Urine Metabolome as Signatures of Soman Poisoning. 2018https://doi.org/10.1101/312660
  12. Amanda S. Appel, Brian A. Logue. Analysis of nerve agent metabolites from nail clippings by liquid chromatography tandem mass spectrometry. Journal of Chromatography B 2016, 1031 , 116-122. https://doi.org/10.1016/j.jchromb.2016.07.034
Download PDF
Go to Analytical Chemistry
Get e-Alerts
Get e-Alerts

Analytical Chemistry

Cite this: Anal. Chem. 2016, 88, 12, 6523–6530
Click to copy citationCitation copied!
https://doi.org/10.1021/acs.analchem.6b01274
Published May 9, 2016

Copyright © 2016 American Chemical Society. This publication is licensed under these Terms of Use.

Request reuse permissions

Article Views

3977

Altmetric

-

Citations

11
Learn about these metrics

Article Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.

Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.

The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated.

  • Abstract

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 1

    Figure 1. Fate of sarin and soman after binding to serine at the active site of AChE (reaction A). Fluoride reactivation of the AChE enzyme is shown in reaction B. Reaction C depicts aging of the agent–enzyme complex. Reaction D represents cleavage of the agent from the enzyme via hydrolysis. Reaction E describes direct hydrolysis of the parent nerve agent. In the figure, R represents the pinacolyl group of soman or the isopropyl group of sarin.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 2

    Figure 2. Parent ion fragmentation observed in negative ESI-MS-MS analysis for (A) PMPA and (B) IMPA.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 3

    Figure 3. Representative chromatograms of PMPA and IMPA spiked hair (near LODs) samples (upper traces) as compared to saline exposed hair samples (lower traces). Internal standard response is not shown.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 4

    Figure 4. Chromatographic analysis of PMPA from exposed rats collected 1 month after exposure, stored, and then analyzed 3.5 years following exposure. PMPA is clearly evident above the LOD in all the GD exposed rats (calculated concentrations ranged from below the LLOQ up to 11.7 μg/kg) and not present in the hair of saline exposed rats.

    High Resolution Image
    Download MS PowerPoint Slide

  • References

    This article references 70 other publications.

    1. 1
      Sidell, F. R.; Tdkafuji, E. T.; Franz, D. R., Eds. Medical Aspects of Chemical and Biological Warfare; Office of the Surgeon General: Falls Church, VA, 1997.
      There is no corresponding record for this reference.
    2. 2
      Munro, N. Environ. Health Perspect. 1994, 102, 18– 38 DOI: 10.1289/ehp.9410218
      There is no corresponding record for this reference.
    3. 3
      Brown, M. A.; Brix, K. A. J. Appl. Toxicol. 1998, 18, 393– 408 DOI: 10.1002/(SICI)1099-1263(199811/12)18:6<393::AID-JAT528>3.0.CO;2-0
      3
      Review of health consequences from high-, intermediate- and low-level exposure to organophosphorus nerve agents
      Brown, Mark A.; Brix, Kelley A.
      Journal of Applied Toxicology (1998), 18 (6), 393-408CODEN: JJATDK; ISSN:0260-437X. (John Wiley & Sons Ltd.)
      A review and discussion with 78 refs. Short and long-term health effects from exposure to organophosphorus (OP) military and insecticidal nerve agents are evaluated based on the abundant scientific literature published over five decades on health effects in humans (from human experimentation and occupational exposures) and in lab. animals. Four distinct health effects are identified: acute cholinergic toxicity; organophosphate-induced delayed neuropathy (OPIDN); subtle long-term neuropsychol. and neurophysiol. effects; and a reversible muscular weakness called "intermediate syndrome". Some effects are subtle and difficult to differentiate from health effects caused by other diseases or occupational exposures. Each effect has data suggesting threshold exposure levels below which it is unlikely to be clin. detectable. Therefore, meaningful interpretation of human and animal studies requires rigid exposure characterization. Because precise exposure levels are often difficult to reconstruct, a system for characterizing exposure is proposed based upon obsd. initial acute signs and symptoms, as high-level (definitive cholinergic poisoning); intermediate-level (threshold cholinergic effects including miosis, rhinorrhea or clin. measurable depression of cholinesterase); and low-level (no immediate clin. signs or symptoms) exposure. Threshold exposure levels for known long-term effects from OP nerve agent are at or above intermediate-level exposure. Long-term health effects seen at intermediate-level exposures or in many survivors of high-level exposure are subtle, detectable in exposed populations but not individuals, and not reported in individuals experiencing low-level exposure alone. Co-exposure to other pharmaceutical agents may promote or protect against health effects from OP nerve agents, but qual. they are the same effects seen with OP nerve agents alone. Thus, the system for characterizing exposure based on initial acute effects is also useful for evaluating health outcomes from co-exposure to OP nerve and other agents.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXnsFSrurw%253D&md5=7c4c693fa1d50f8e6450b24f8e617db9
    4. 4
      DeCaprio, A. P., Ed. Toxicologic Biomarkers; Taylor & Francis Group: New York, 2006.
      There is no corresponding record for this reference.
    5. 5
      Desoubries, C.; Chapuis-Hugon, F.; Bossée, A.; Pichon, V. J. Chromatogr. B: Anal. Technol. Biomed. Life Sci. 2012, 900, 48– 58 DOI: 10.1016/j.jchromb.2012.05.029
      5
      Three-phase hollow fiber liquid-phase microextraction of organophosphorous nerve agent degradation products from complex samples
      Desoubries, Charlotte; Chapuis-Hugon, Florence; Bossee, Anne; Pichon, Valerie
      Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences (2012), 900 (), 48-58CODEN: JCBAAI; ISSN:1570-0232. (Elsevier B.V.)
      Degrdn. products of chem. warfare agents are considered as important environmental and biol. markers of chem. attacks. Alkyl methylphosphonic acids (AMPAs), resulting from the fast hydrolysis of nerve agents, such as sarin and soman, and the methylphosphonic acid (MPA), final degrdn. product of AMPAs, were detd. from complex matrixes by using an emergent and miniaturized extn. technique, the hollow fiber liq.-phase microextn. (HF-LPME), before their anal. by liq. chromatog. coupled to mass spectrometry (LC-MS). After studying different conditions of sepn. in the reversed phase LC-MS anal., the sample treatment method was set up. The three-phase HF-LPME was carried out by using a porous polypropylene (PP) hollow fiber impregnated with 1-octanol that separates the donor and acceptor aq. media. Various extn. parameters were evaluated such as the vol. of the sample, the effect of the pH and the salt addn. to the sample, the pH of the acceptor phase, the extn. temp., the stirring speed of the sample, the immersion time in the org. solvent and the time of extn. The optimum conditions were applied to the detn. of MPA and five AMPAs in real samples, such as surface waters and urine. Compds. were extd. from a 3 mL acidified sample into only 6 μL of alk. water without any other pretreatment of the complex matrixes. Enrichment factors (EFs) higher than 170 were obtained for three less polar AMPAs. Limits of quantification (LOQs) in the 0.013-5.3 ng mL-1 range were obtained after microextn. of AMPAs from river water and in the range of 0.056-4.8 ng mL-1 from urine samples with RSD values between 1 and 9%.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XpsV2ntL8%253D&md5=161f83560980f4629232b5795cc7f240
    6. 6
      Rodin, I.; Braun, A.; Stavrianidi, A.; Baygildiev, T.; Shpigun, O.; Oreshkin, D.; Rybalchenko, I. J. Anal. Toxicol. 2015, 39, 69– 74 DOI: 10.1093/jat/bku119
      6
      'Dilute-and-shoot' RSLC-MS-MS method for fast detection of nerve and vesicant chemical warfare agent metabolites in urine
      Rodin Igor; Braun Arcady; Stavrianidi Andrey; Baygildiev Timur; Shpigun Oleg; Oreshkin Dmitry; Rybalchenko Igor
      Journal of analytical toxicology (2015), 39 (1), 69-74 ISSN:.
      A sensitive screening method based on fast liquid chromatography tandem mass-spectrometry (RSLC-MS-MS) has shown the feasibility of separation and detection of low concentration β-lyase metabolites of sulfur mustard and of nerve agent phosphonic acids in urine. The analysis of these compounds is of interest because they are specific metabolites of the chemical warfare agents (CWAs), sulfur mustard (HD), sarin (GB), soman (GD), VX and Russian VX (RVX). The 'dilute-and-shoot' RSLC-MS-MS method provides a sensitive and direct approach for determining CWA exposure in non-extracted non-derivatized samples from urine. Chromatographic separation of the metabolites was achieved using a reverse phase column with gradient mobile phases consisting of 0.5% formic acid in water and acetonitrile. Identification and quantification of species were achieved using electrospray ionization-tandem mass-spectrometry monitoring two precursor-to-product ion transitions for each compound. The method demonstrates linearity over at least two orders of magnitude and had detection limits of 0.5 ng/mL in urine.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC2M3hsFKlsQ%253D%253D&md5=094e0aedfc3d1bfd3f6a059bec6d281a
    7. 7
      Shih, M.; McMonagle, J.; Dolzine, T.; Gresham, V. J. Appl. Toxicol. 1994, 14, 195– 199 DOI: 10.1002/jat.2550140309
      7
      Metabolite pharmacokinetics of soman, sarin and GF in rats and biological monitoring of exposure to toxic organophosphorus agents
      Shih, Ming L.; McMonagle, Joseph D.; Dolzine, Theodore W.; Gresham, Vincent C.
      Journal of Applied Toxicology (1994), 14 (3), 195-9CODEN: JJATDK; ISSN:0260-437X.
      This study reports on the pharmacokinetics of the elimination of the metabolites of three toxic organophosphorus compds. (soman, sarin and GF). Urine, blood and lung tissue were collected from rats dosed s.c. at 75 μg kg-1. Urinary excretion of the metabolite was the major elimination route for these three compds. The major differences among them were primarily the extent and rate of excretion. The hydrolyzed form, alkylmethylphosphonic acid, was the single major metabolite formed and excreted in urine by a non-saturable mechanism. Nearly total recoveries of the given doses for sarin and GF in metabolite form were obtained from the urine. The terminal elimination half-lives in urine were 3.7 ± 0.1 and 9.9 ± 0.8 h for sarin and GF, resp. Soman metabolite showed a biphasic elimination curve with terminal half-lives of 18.5 ± 2.7 and 3.6 ± 2.2 h. Soman was excreted at a slower rate with a recovery of only 62%. Lung was the major organ of accumulation for soman. In blood the toxic agents were concd. more in red blood cells than in plasma. The acid metabolites can serve as a better chem. marker for monitoring organophosphorus exposure in humans via their higher concn. and longer half-life in urine than the parent compds.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2cXkt1yrtrY%253D&md5=ea0bce98d782d4c7fd5af48ee876144a
    8. 8
      Minami, M.; Hui, D.; Katsumata, M.; Inagaki, H.; Boulet, C. J. Chromatogr., Biomed. Appl. 1997, 695, 237– 244 DOI: 10.1016/S0378-4347(97)00203-X
      8
      Method for the analysis of the methylphosphonic acid metabolites of sarin and its ethanol-substituted analog in urine as applied to the victims of the Tokyo sarin disaster
      Minami, Masayasu; Hui, Da-Mei; Katsumata, Masao; Inagaki, Hirofumi; Boulet, Camille A.
      Journal of Chromatography B: Biomedical Sciences and Applications (1997), 695 (2), 237-244CODEN: JCBBEP; ISSN:0378-4347. (Elsevier)
      An anal. method for the methylphosphonic acid metabolites of sarin in urine using trimethylsilyl derivatization and flame photometric detection is described in this report. Authentic ref. stds. of iso-Pr methylphosphonic acid (IMPA) and Et methylphosphonic acid (EMPA) as well as methylphosphonic acid were employed to est. the concn. in human urine. A sample pretreatment procedure was developed for urine using a column of cation-loaded ion-exchange resins (Ag+-, Ba2+- or H+-Dowex) and adjusting the pH of the eluate from the column to 3.75-3.85 improved recovery of the target compds. The eluate was evapd. to dryness under vacuum prior to trimethylsilylation, to remove water and any hydroxy- or amino-carrying volatile substances. The sarin metabolites, because of their low volatility, were concd. and could be derivatized for anal. The use of synthesized authentic sarin and ethylsarin metabolites, i.e., IMPA and EMPA, made it possible to establish the necessary sample pretreatment procedures for derivatization and gas chromatog.-flame photometric detection (GC-FPD) anal. The detection limits were 0.025 ppm both for EMPA and IMPA, and 0.625 μM for MPA, resp. This method can be useful for estg. the exposure level to sarin by assaying the metabolites in urine and it is applicable to a large nos. of samples.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXks12lu7w%253D&md5=378454be3ba8b20787cc2a4ced0847df
    9. 9
      Fredriksson, S.-A.; Hammarstrom, L.-G.; Henriksson, L.; Lakso, H.-A. J. Mass Spectrom. 1995, 30, 1133– 1143 DOI: 10.1002/jms.1190300810
      9
      Trace determination of alkyl methylphosphonates in environmental and biological samples using gas chromatography/negative-ion chemical ionization mass spectrometry and tandem mass spectrometry
      Fredriksson, Sten-Aake; Hammerstroem, Lars-Gunnar; Henriksson, Liselott; Lakso, Hans-Aake
      Journal of Mass Spectrometry (1995), 30 (8), 1133-43CODEN: JMSPFJ; ISSN:1076-5174. (Wiley)
      Alkyl methylphosphonates (I) are metabolites and primary hydrolysis products of the organophosphorus nerve agents listed in the Chem. Weapons Convention. Gas chromatog./neg.-ion chem. ionization mass spectrometry and tandem mass spectrometry (GC/NICI-MS and GC/NICI-MS/MS) were used for the detn. of I as their pentafluorobenzyl esters. Extremely high sensitivity was obtained and low attogram amts. could be detected by GC/NICI-MS. Ion-exchange chromatog. was employed for selective isolation and enrichment of I in serum, urine, water and soil samples. Collision-induced dissocn. (CID) of the single methylphosphonate anion peak from NICI of the pentafluorobenzyl ester produced fragment ions specific for the methylphosphonate structure, allowing pos. identification of I. CID conditions optimized for structure information and for sensitivity were investigated. The improved selectivity of GC/MS/MS allows the detection of femtogram amts. of I in samples where chem. background inhibits detection by GC/MS.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2MXnsFajtb0%253D&md5=fbb6ca0442228686df72c9b04a4013cb
    10. 10
      Noort, D.; Hulst, A.; Platenburg, D.; Polhuijs, M.; Benschop, H. Arch. Toxicol. 1998, 72, 671– 675 DOI: 10.1007/s002040050559
      10
      Quantitative analysis of O-isopropyl methylphosphonic acid in serum samples of Japanese citizens allegedly exposed to sarin: estimation of internal dosage
      Noort, Daan; Hulst, Albert G.; Platenburg, Dominique H. J. M.; Polhuijs, Martine; Benschop, Hendrik P.
      Archives of Toxicology (1998), 72 (10), 671-675CODEN: ARTODN; ISSN:0340-5761. (Springer-Verlag)
      A convenient and rapid micro-anion exchange liq. chromatog. (LC) tandem electrospray mass spectrometry (MS) procedure was developed for quant. anal. in serum of O-iso-Pr methylphosphonic acid (IMPA), the hydrolysis product of the nerve agent sarin. The mass spectrometric procedure involves neg. or pos. ion electrospray ionization and multiple reaction monitoring (MRM) detection. The method could be successfully applied to the anal. of serum samples from victims of the Tokyo subway attack and of an earlier incident at Matsumoto, Japan. IMPA levels ranging from 2 to 135 ng/mL were found. High levels of IMPA appear to correlate with low levels of residual butyrylcholinesterase activity in the samples and vice versa. Based on our analyses, the internal and exposure doses of the victims were estd. In several cases, the doses appeared to be substantially higher than the assumed LDs in man.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXmvFCqtLo%253D&md5=4dd87f7705d0707e52f27fa9e9002066
    11. 11
      Evans, R.; Jakubowski, E.; Muse, W.; Matson, K.; Hulet, S.; Mioduszewski, R.; Thomson, S.; Totura, A.; Renner, J.; Crouse, C. J. Anal. Toxicol. 2008, 32, 78– 85 DOI: 10.1093/jat/32.1.78
      11
      Quantification of Sarin and Cyclosarin Metabolites Isopropyl Methylphosphonic Acid and Cyclohexyl Methylphosphonic Acid in Minipig Plasma Using Isotope-Dilution and Liquid Chromatography- Time-of-Flight Mass Spectrometry
      Evans, R. A.; Jakubowski, E. M.; Muse, W. T.; Matson, K.; Hulet, S. W.; Mioduszewski, R. J.; Thomson, S. A.; Totura, A. L.; Renner, J. A.; Crouse, C. L.
      Journal of Analytical Toxicology (2008), 32 (1), 78-85CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
      An anal. method for detg. iso-Pr methylphosphonic acid (IMPA) and cyclohexyl methylphosphonic acid (CMPA), the metabolic hydrolysis products of toxic organophosphorus nerve agents iso-Pr methylphosphonofluoridate (sarin, GB) and cyclohexyl methylphosphonofluoridate (cyclosarin, GF), resp., has been developed and validated using high-performance liq. chromatog.-mass spectrometry with neg. ion electrospray ionization with time-of-flight detection (LC-ESI-MS-TOF). The linear range of quantitation was 5 to 125 ng/mL in plasma with a method detection limit of 2 ng/mL for each compd. This method was developed to det. the amt. of metabolic hydrolysis that was formed during and after nerve agent exposure in minipigs to account for a major pathway of GB and GF elimination that had not been previously characterized in the bloodstream, particularly during low-level whole-body inhalation expts. Metabolic hydrolysis accounted for 70% to 90% of the recoverable agent in the bloodstream during exposure, when compared to both unbound and cholinesterase bound agent recovered by fluoride ion reactivation anal. for the same samples. The estd. half-life of IMPA and CMPA in plasma was detd. to be 44 and 61 min, resp. The method utilizes the mass selectivity of LC-ESI-MS-TOF using a bench-top instrument to achieve a detection limit that is consistent with reported LC-MS-MS methods analyzing blood samples. (c) 2008 Preston Publications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1cXhtFertr0%253D&md5=d7a321106c5a2fccd2647f05b08a462c
    12. 12
      Røen, B. T.; Sellevåg, S. R.; Lundanes, E. Anal. Chem. 2014, 86, 11833– 11840 DOI: 10.1021/ac503408x
      There is no corresponding record for this reference.
    13. 13
      Abney, C. W.; Knaack, J. L.; Ali, A. A.; Johnson, R. C. Chem. Res. Toxicol. 2013, 26, 775– 782 DOI: 10.1021/tx4000717
      There is no corresponding record for this reference.
    14. 14
      van der Meer, J.; Trap, H.; Noort, D.; van der Schans, M. J. Chromatogr. B: Anal. Technol. Biomed. Life Sci. 2010, 878, 1320– 1325 DOI: 10.1016/j.jchromb.2010.02.019
      14
      Comprehensive gas chromatography with Time of Flight MS and large volume introduction for the detection of fluoride-induced regenerated nerve agent in biological samples
      van der Meer, J. A.; Trap, H. C.; Noort, D.; van der Schans, M. J.
      Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences (2010), 878 (17-18), 1320-1325CODEN: JCBAAI; ISSN:1570-0232. (Elsevier B.V.)
      Recently, several methods were developed to verify exposure to nerve agents. Most of these methods, such as the fluoride reactivation technique and the anal. of inhibited phosphonylated butyrylcholinesterase (BuChE), are based on mass spectrometry. The high specificity of the mass spectrometer might also imply a disadvantage, because the acquisition mass, i.e. the identity of the analyte must be known beforehand to direct the MS anal. in the most sensitive mode. In real cases, the identity of the nerve agent is not always known beforehand and the mass spectrometer should be operated in a scanning mode, with the consequence that sensitivity of the method will be lower. Comprehensive GC, or GC × GC, is a technique which offers enhanced sepn. The implied larger selectivity of the GC sepn. allows mass spectrometry to be conducted in a less specific, scanning, mode. By the use of this configuration, the identity of the nerve agent does not have to be known beforehand but can be traced. In order to be able to detect lower concns. and assess lower exposure levels, a large vol. injection technique was developed allowing sample sizes up to 100 μL. The technique was tested with plasma samples that had been inhibited with various nerve agents. Subsequently, the cholinesterase-bound nerve agent was regenerated by the fluoride reactivation technique. Using the newly developed comprehensive GC-MS method it was possible to detect nerve agent at an exposure level of 1% BuChE inhibition, which is approx. 70 pg nerve agent/mL. These low exposure levels cannot be verified with a cholinesterase (ChE) activity assay. Moreover, the identity of the regenerated nerve agent was verified by the mass spectrum that was generated by the TOF mass spectrometer. This paper presents a technique able to deliver full-scan data on the anal. of nerve agents in biomedical samples at relevant exposure levels (1% BuChE inhibition). This full-scan data meets for a large part the forensic requirements that are in place for the anal. of biomedical samples in the context of alleged use of Chem. Warfare Agents.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXlt1GmtLc%253D&md5=991c2e3c88602b0f612852b7f5fbbb51
    15. 15
      Polhuijs, M.; Langenberg, J. P.; Benschop, H. P. Toxicol. Appl. Pharmacol. 1997, 146, 156– 161 DOI: 10.1006/taap.1997.8243
      15
      New method for retrospective detection of exposure to organophosphorus anticholinesterases: application to alleged sarin victims of Japanese terrorists
      Polhuijs, Martine; Langenberg, Jan P.; Benschop, Hendrik P.
      Toxicology and Applied Pharmacology (1997), 146 (1), 156-161CODEN: TXAPA9; ISSN:0041-008X. (Academic)
      With regard to detection of exposure to anticholinesterase, the presently used methods have the disadvantage that they cannot detect either low-level exposures with certainty or the structure of the agent and the extent of poisoning. 4In principle, organophosphate-inhibited butyrylcholinesterase in human plasma is the most persistent and abundant source for biomonitoring of exposure to organophosphate anticholinesterases. Fluoride ions reactivate the inhibited enzyme readily at pH 4, converting the organophosphate moiety into the corresponding phosphofluoridate. Subsequent quantitation of the latter product provides a reliable, highly sensitive and retrospective method for detection of exposure to, or handling of, organophosphates such as nerve agents and organophosphorus pesticides. The authors applied the new procedure to serum samples from victims of the Tokyo subway attack by the AUM Shinriyko sect and from an earlier incident at Matsumoto. In serum of 10 of 11 victims from the Tokyo incident and of 2 of the 7 samples from the Matsumoto incident, reactivation with fluoride ions yielded sarin concns. in the range of 0.2-4.1 ng/mL serum. Evidently, these victims had been exposed to an organophosphate with the structure PriO(CH3)P(O)X, presumably with X = F (sarin). Several applications of the new procedure to establish nerve agent and/or organophosphate (OP) pesticide exposure can be envisaged, e.g., (i) in biomonitoring of exposure for health surveillance of those handling organophosphates, (ii) in cases of alleged exposure to nerve agents and/or OP pesticides in armed conflict situations or terrorist attacks, (iii) in medical treatment of intoxication, and (i.v.) in forensic cases against suspected terrorists that may have handled anticholinesterases.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXmt1Wgsb0%253D&md5=0f845cde04dad82b9ec8be1779d7c5e1
    16. 16
      Adams, T.; Capacio, B.; Smith, J.; Whalley, C.; Korte, W. Drug Chem. Toxicol. 2005, 27, 77– 91 DOI: 10.1081/DCT-120027901
      There is no corresponding record for this reference.
    17. 17
      Lee, J. Y.; Lee, Y. H. Int. J. Anal. Mass Spectrom. Chromatogr. 2014, 2, 65 DOI: 10.4236/ijamsc.2014.23007
      There is no corresponding record for this reference.
    18. 18
      Sporty, J. L.; Lemire, S. W.; Jakubowski, E. M.; Renner, J. A.; Evans, R. A.; Williams, R. F.; Schmidt, J. G.; Schans, M. J. v. d.; Noort, D.; Johnson, R. C. Anal. Chem. 2010, 82, 6593– 6600 DOI: 10.1021/ac101024z
      There is no corresponding record for this reference.
    19. 19
      Carter, M. D.; Crow, B. S.; Pantazides, B. G.; Watson, C. M.; Thomas, J. D.; Blake, T. A.; Johnson, R. C. Anal. Chem. 2013, 85, 11106– 11111 DOI: 10.1021/ac4029714
      There is no corresponding record for this reference.
    20. 20
      Crow, B. S.; Pantazides, B. G.; Quiñones-González, J.; Garton, J. W.; Carter, M. D.; Perez, J. W.; Watson, C. M.; Tomcik, D. J.; Crenshaw, M. D.; Brewer, B. N. Anal. Chem. 2014, 86, 10397– 10405 DOI: 10.1021/ac502886c
      There is no corresponding record for this reference.
    21. 21
      Fidder, A.; Hulst, A.; Noort, D.; de Ruiter, R.; van der Schans, M.; Benschop, H.; Langenberg, J. Chem. Res. Toxicol. 2002, 15, 582– 590 DOI: 10.1021/tx0101806
      There is no corresponding record for this reference.
    22. 22
      Che, M. M.; Conti, M.; Boylan, M.; Sciuto, A. M.; Gordon, R. K.; Nambiar, M. P. Inhalation Toxicol. 2008, 20, 821– 828 DOI: 10.1080/08958370802050957
      22
      Blood and Bronchoalveolar Lavage Fluid Acetylcholinesterase Levels Following Microinstillation Inhalation Exposure to Sarin in Guinea Pigs
      Che, Magnus M.; Conti, Michele; Boylan, Megan; Sciuto, Alfred M.; Gordon, Richard K.; Nambiar, Madhusoodana P.
      Inhalation Toxicology (2008), 20 (9), 821-828CODEN: INHTE5; ISSN:0895-8378. (Informa Healthcare)
      The authors detd. acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition in the bronchoalveolar lavage fluid (BALF) following inhalation exposure to chem. threat nerve agent (CTNA) sarin. Age- and wt.-matched male guinea pigs were exposed to 5 different doses of sarin (169.3, 338.7, 508, 677.4, and 846.5 mg/m3) using a microinstillation inhalation exposure technique for 4 min. The technique involves aerosolization of the agent in the trachea using a microcatheter with a center hole that delivers the agent and multiple peripheral holes that pumps air to aerosolize the agent at the tip. Animals exposed to higher doses of sarin occasionally developed seizures and succumbed to death within 15 min after exposure. The LCt50 for sarin using the microinstillation technique was detd. to be close to 677.4 mg/m3. Ear blood AChE activity showed a dose-dependent inhibition at 15 min postexposure. The inhibition of blood AChE remained const. over 35 and 55 min after sarin exposure indicating that there was no lung depot effect. Cardiac blood AChE and butyrylcholinesterase (BChE) activity in surviving animals euthanized at 24 h postexposure showed a dose-dependent inhibition with an inhibition of 60% at 677.4 and 846.5 mg/m3 sarin exposure. AChE and BChE activity in bronchoalveolar lavage fluid (BALF) showed a slight increase at 338.7-677.4 mg/m3 sarin exposure but a marginal inhibition at 169.3 mg/m3. In contrast, the AChE protein levels detd. by immunoblotting showed an increase at 169.3 mg/m3 in the BALF. The BALF protein level, a biomarker of lung injury, was increased maximally at 338.7 mg/m3 and that increase was dropped with an increase in the dose of sarin. The BALF protein levels correlated with the AChE and BChE activity. These data suggest that sarin microinstillation inhalation exposure results in respiratory toxicity and lung injury characterized by changes in lavage AChE, BChE, and protein levels.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1cXoslWqtbk%253D&md5=2ab6248389a63391554448f205726996
    23. 23
      Read, R.; Riches, J.; Stevens, J.; Stubbs, S.; Black, R. Arch. Toxicol. 2010, 84, 25– 36 DOI: 10.1007/s00204-009-0473-4
      23
      Biomarkers of organophosphorus nerve agent exposure: comparison of phosphylated butyrylcholinesterase and phosphylated albumin after oxime therapy
      Read, Robert W.; Riches, James R.; Stevens, Jacqueline A.; Stubbs, Sarah J.; Black, Robin M.
      Archives of Toxicology (2010), 84 (1), 25-36CODEN: ARTODN; ISSN:0340-5761. (Springer)
      Organophosphorus nerve agents inhibit the activity of cholinesterases by phosphylation of the active site serine. In addn., sarin, cyclosarin, soman and tabun have been shown to phosphylate a tyrosine residue in albumin. Therapies against nerve agent poisoning include the use of oximes to reactivate inhibited cholinesterases by displacement of the phosphyl moiety and hence detectable levels of adducts with cholinesterases may be reduced. Adducts with tyrosine have been shown to be persistent in the guinea pig in the presence of oxime therapy. Plasma samples obtained from an animal study aimed at improving therapy against nerve agent poisoning were used to compare the suitability of tyrosine and butyrylcholinesterase (BuChE) adducts as biomarkers of nerve agent exposure after treatment with therapeutic oximes. Under the terms of the project licence, these samples could be collected only on death of the animal, which occurred within hours of exposure or when culled at 23 or 24 days. Tyrosine adducts were detected in all samples collected following intra-muscular administration of twice the LD50 dose of the resp. nerve agent. Aged BuChE adducts were detected in samples collected within a few hours after administration of soman and tabun, but not after 23 or 24 days. No BuChE adducts were detected in animals exposed to sarin and cyclosarin where samples were collected only after 23 or 24 days.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXhtlanu7fO&md5=f0bd78020cc8453e483ea425eb30726f
    24. 24
      Bao, Y.; Liu, Q.; Chen, J.; Lin, Y.; Wu, B.; Xie, J. J. Chromatogr. A 2012, 1229, 164– 171 DOI: 10.1016/j.chroma.2012.01.032
      There is no corresponding record for this reference.
    25. 25
      Chen, S.; Zhang, J.; Lumley, L.; Cashman, J. R. J. Pharmacol. Exp. Ther. 2013, 344, 531– 541 DOI: 10.1124/jpet.112.201368
      25
      Immunodetection of serum albumin adducts as biomarkers for organophosphorus exposure
      Chen, Sigeng; Zhang, Jun; Lumley, Lucill; Cashman, John R.
      Journal of Pharmacology and Experimental Therapeutics (2013), 344 (2), 531-541CODEN: JPETAB; ISSN:1521-0103. (American Society for Pharmacology and Experimental Therapeutics)
      A major challenge in organophosphate (OP) research has been the identification and utilization of reliable biomarkers for the rapid, sensitive, and efficient detection of OP exposure. Although Tyr 411 OP adducts to human serum albumin (HSA) have been suggested to be one of the most robust biomarkers in the detection of OP exposure, the anal. of HSA-OP adduct detection has been limited to techniques using mass spectrometry. Herein, we describe the procurement of two monoclonal antibodies (mAb-HSA-GD and mAb-HSA-VX) that recognized the HSA Tyr 411 adduct of soman (GD) or S-[2-(diisopropylamino)ethyl]-O-Et methylphosphonothioate (VX), resp., but did not recognize nonphosphonylated HSA. We showed that mAb-HSA-GD was able to detect the HSA Tyr 411 OP adduct at a low level (i.e., human blood plasma treated with 180 nM GD) that could not be detected by mass spectrometry. MAb-HSA-GD and mAb-HSA-VX showed an extremely low-level detection of GD adducted to HSA (on the order of picograms). MAb-HSA-GD could also detect serum albumin OP adducts in blood plasma samples from different animals administered GD, including rats, guinea pigs, and monkeys. The ability of the two antibodies to selectively recognize nerve agents adducted to serum albumin suggests that these antibodies could be used to identify biomarkers of OP exposure and provide a new biol. approach to detect OP exposure in animals.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXhsFKhsrs%253D&md5=aa629bba77bcf91bb175e1469c55e4c9
    26. 26
      Williams, N.; Harrison, J.; Read, R.; Black, R. Arch. Toxicol. 2007, 81, 627– 639 DOI: 10.1007/s00204-007-0191-8
      26
      Phosphylated tyrosine in albumin as a biomarker of exposure to organophosphorus nerve agents
      Williams, Nichola H.; Harrison, John M.; Read, Robert W.; Black, Robin M.
      Archives of Toxicology (2007), 81 (9), 627-639CODEN: ARTODN; ISSN:0340-5761. (Springer)
      The organophosphorus nerve agents sarin, soman, cyclosarin and tabun phosphylate a tyrosine residue on albumin in human blood. These adducts may offer relatively long-lived biol. markers of nerve agent exposure that do not 'age' rapidly, and which are not degraded by therapy with oximes. Sensitive methods for the detection of these adducts have been developed using liq. chromatog.-tandem mass spectrometry. Adducts of all four nerve agents were detected in the blood of exposed guinea pigs being used in studies to improve medical countermeasures. The tyrosine adducts with soman and tabun were detected in guinea pigs receiving therapy 7 days following s.c. administration of five times the LD50 dose of the resp. nerve agent. VX also forms a tyrosine adduct in human blood in vitro but only at high concns.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXosFarsLc%253D&md5=a288265a5ff20941a6392c4d597e701e
    27. 27
      Nagao, M.; Takatori, T.; Matsuda, Y.; Nakajima, M.; Iwase, H.; Iwadate, K. Toxicol. Appl. Pharmacol. 1997, 144, 198– 203 DOI: 10.1006/taap.1997.8110
      27
      Definitive evidence for the acute sarin poisoning diagnosis in the Tokyo subway
      Nagao, Masataka; Takatori, Takehiko; Matsuda, Yukimasa; Nakajima, Makoto; Iwase, Hirotaro; Iwadate, Kimiharu
      Toxicology and Applied Pharmacology (1997), 144 (1), 198-203CODEN: TXAPA9; ISSN:0041-008X. (Academic)
      A new method was developed to detect sarin hydrolysis products from the erythrocytes of 4 victims of sarin (isopropylmethylphosphonofluoridate) poisoning resulting from the terrorist attack on the Tokyo subway. Sarin-bound acetylcholinesterase (AChE) was solubilized from the erythrocyte membranes of sarin victims, digested with trypsin, the sarin hydrolysis products bound to AChE were released by alk. phosphatase digestion, and the digested sarin hydrolysis products were subjected to trimethylsilyl derivatization and detected by gas chromatog.-mass spectrometry. Isopropylmethylphosphonic acid, which is a sarin hydrolysis product, was detected in all sarin poisoning victims examd. and methylphosphonic acid, which is a sarin and soman hydrolysis product, was detd. in all victims. Postmortem examns. revealed no macroscopic and microscopic findings specific to sarin poisoning and sarin and its hydrolysis products were almost undetectable in their blood. Thus, the procedure described is useful for the forensic diagnosis of acute sarin poisoning.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXivFKhur4%253D&md5=eb701b0d8553559b49733a7c5ead7215
    28. 28
      Tsuchihashi, H.; Katagi, M.; Nishikawa, M.; Tatsuno, M. J. Anal. Toxicol. 1998, 22, 383– 388 DOI: 10.1093/jat/22.5.383
      28
      Identification of metabolites of nerve agent VX in serum collected from a victim
      Tsuchihashi, Hitoshi; Katagi, Munehiro; Nishikawa, Mayumi; Tatsuno, Michiaki
      Journal of Analytical Toxicology (1998), 22 (5), 383-388CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
      A human serum sample collected from a victim of the Osaka VX incident was analyzed according to our developed technique for metabolites of VX. Gas chromatog.-mass spectrometry (GC-MS) in full-scan electron impact and chem. ionization modes were used, and, for more reliable confirmation, GC-MS-MS was also employed. In the serum sample, both Et methylphosphonic acid and 2-(diisopropylaminoethyl) Me sulfide were detected. These results indicated that the techniques using GC-MS and GC-MS-MS were applicable to biol. samples such as serum. These results also provide the first documented, unequivocal identification of the specific metabolites of VX in victim's serum and, furthermore, clarify a part of the metabolic pathway of VX in the human body.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXlvFaru7s%253D&md5=3817821c5624ab1188335390d901cd36
    29. 29
      Nagao, M.; Takatori, T.; Matsuda, Y.; Nakajima, M.; Niijima, H.; Iwase, H.; Iwadate, K.; Amano, T. J. Chromatogr., Biomed. Appl. 1997, 701, 9– 17 DOI: 10.1016/S0378-4347(97)00355-1
      29
      Detection of sarin hydrolysis products from sarin-like organophosphorus agent-exposed human erythrocytes
      Nagao, Masataka; Takatori, Takehiko; Matsuda, Yukimasa; Nakajima, Makoto; Niijima, Hitoshi; Iwase, Hirotaro; Iwadate, Kimiharu; Amano, Toshikimi
      Journal of Chromatography B: Biomedical Sciences and Applications (1997), 701 (1), 9-17CODEN: JCBBEP; ISSN:0378-4347. (Elsevier)
      A sarin-like organophosphorus agent, [bis(iso-Pr methylphosphonate); BIMP], was synthesized. This agent has the same phosphonate group as sarin and also has the same anti-acetylcholinesterase activity potency as sarin. The ID50 and LD50 values of BIMP in mice after i.v. injection were 3.9 nM and 0.8 mg/kg, resp. The AChE activities of their red blood cells and brains were dose-dependently reduced by i.v. BIMP. After prepn. of exptl. BIMP-exposed human red blood cells, BIMP-bound acetylcholinesterase (AChE) was solubilized from erythrocyte membranes, purified by immunoaffinity chromatog., digested with trypsin, and the sarin hydrolysis products bound to AChE were released by alk. phosphatase digestion. The digested sarin hydrolysis products were subjected to trimethylsilyl (TMS) derivatization and detected by gas chromatog.-mass spectrometry. Iso-Pr methylphosphonic- and methylphosphonic acids, which are the sarin hydrolysis products, were detected in exptl. BIMP-exposed human red blood cells. This new method, which enables sarin's hydrolysis products to be detected in BIMP-exposed erythrocytes, is a useful tool for studying sarin-poisoning victims.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXntVOntrs%253D&md5=acc6ca592545c8d421f6b5e25a4617ff
    30. 30
      Bajgar, J. Occup. Environ. Med. 1992, 49, 648– 653 DOI: 10.1136/oem.49.9.648
      There is no corresponding record for this reference.
    31. 31
      Degenhardt, C.; Pleijsier, K.; van der Schans, M.; Langenberg, J.; Preston, K.; Solano, M.; Maggio, V.; Barr, J. J. Anal. Toxicol. 2004, 28, 364– 371 DOI: 10.1093/jat/28.5.364
      31
      Improvements of the Fluoride Reactivation Method for the Verification of Nerve Agent Exposure
      Degenhardt, Carla E. A. M.; Pleijsier, Kees; van der Schans, Marcel J.; Langenberg, Jan P.; Preston, Kerry E.; Solano, Maria I.; Maggio, V. L.; Barr, John R.
      Journal of Analytical Toxicology (2004), 28 (5), 364-371CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
      One of the most appropriate biomarkers for the verification of organophosphorus nerve agent exposure is the conjugate of the nerve agent to butyrylcholinesterase (BuChE). The phosphyl moiety of the nerve agent can be released from the BuChE enzyme by incubation with fluoride ions, after which the resulting organophosphonofluoridate can be analyzed with gas chromatog.-mass spectrometry (GC-MS). This paper describes recent improvements of the fluoride-induced reactivation in human plasma or serum samples by enhancing the sample prepn. with new solid-phase extn. cartridges and the MS anal. with large vol. injections. Anal. is performed with thermal desorption GC with either mass selective detection with ammonia chem. ionization or high-resoln. MS with electron impact ionization. The organophosphorus chem. warfare agents analyzed in this study are O-Et S-2-diisopropylaminoethyl methylphosphonothiolate, Et methylphosphonofluoridate, iso-Pr methylphosphonofluoridate (sarin, GB), O-Et N,N-dimethylphosphoramidocyanidate, Et N,N-dimethylphosphoramidofluoridate, and cyclohexyl methylphosphonfluoridate. Detection limits of approx. 10 pg/mL plasma were achieved for all analytes, which corresponds to 0.09% inhibition with GB on a sample with normal BuChE levels. (c) 2004 Preston Publications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXlsFKmsLk%253D&md5=f0e49a371114cc340a7b44841bf2eef8
    32. 32
      Wenthold, R.; Mahler, H.; Moore, W. J. Neurochem. 1974, 22, 941– 943 DOI: 10.1111/j.1471-4159.1974.tb04319.x
      32
      Half-life of acetylcholinesterase in mature rat brain
      Wenthold, R. J.; Mahler, H. R.; Moore, W. J.
      Journal of Neurochemistry (1974), 22 (6), 941-3CODEN: JONRA9; ISSN:0022-3042.
      The rate of degrdn. of acetylcholinesterase (EC 3.1.1.7) in mature rat cerebral cortex was detd. from the time course of the label introduced into the protein by 1 intraventricular injection of L-leucine-1-14C. The half-life of the enzyme was 2.84 days.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaE2cXltFOkt7Y%253D&md5=b322175ebf861e6ca5118083dda124f3
    33. 33
      Rotundo, R. L.; Fambrough, D. M. Cell 1980, 22, 583– 594 DOI: 10.1016/0092-8674(80)90368-2
      There is no corresponding record for this reference.
    34. 34
      Maxwell, D. M.; Castro, C. A.; De La Hoz, D. M.; Gentry, M. K.; Gold, M. B.; Solana, R. P.; Wolfe, A. D.; Doctor, B. P. Toxicol. Appl. Pharmacol. 1992, 115, 44– 49 DOI: 10.1016/0041-008X(92)90365-Y
      34
      Protection of rhesus monkeys against soman and prevention of performance decrement by pretreatment with acetylcholinesterase
      Maxwell, Donald M.; Castro, Carl A.; De la Hoz, Denise M.; Gentry, Mary K.; Gold, Mark B.; Solana, Richard P.; Wolfe, Alan D.; Doctor, Bhupendra P.
      Toxicology and Applied Pharmacology (1992), 115 (1), 44-9CODEN: TXAPA9; ISSN:0041-008X.
      The ability of acetylcholinesterase from fetal bovine serum (FBS AChE) to protect against soman, a highly toxic organophosphorus (OP) compd., was tested in Rhesus monkeys. I.v. administration of FBS AChE produced a minimal behavioral effect on the serial probe recognition task, a sensitive test of cognitive function and short-term memory. Pharmacokinetic studies of injected FBS AChE indicated a plasma half-life of 40 h for FBS AChE in monkeys. In vitro and in vivo titrn. of FBS AChE with soman produced a 1:1 stoichiometry between organophosphate-inhibited FBS AChE and the cumulative dose of the toxic stereoisomers of soman. Administration of FBS AChE protected monkeys against the lethal effects of up to 2.7 LD50 of soman and prevented any signs of organophosphate intoxication, e.g., excessive secretions, respiratory depression, muscle fasciculations, or convulsions. In addn., monkeys pretreated with FBS AChE were devoid of any behavioral incapacitation after soman challenge, as measured by the serial probe recognition task. Compared to the current multicomponent drug treatment against soman, which does not prevent the signs or the behavioral deficits resulting from OP intoxication, use of FBS AChE as a single pretreatment drug provides significantly effective protection against both the lethal and the behavioral effects of soman.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK38XltVGqs7c%253D&md5=7884cbb25abd24f3d27daff9193d0bf7
    35. 35
      Hall, G. M.; Woods, G. J.; Patterson, J. L. Br. J. Anaesth. 1984, 56, 903– 904 DOI: 10.1093/bja/56.8.903
      35
      Half-life of plasma cholinesterase
      Hall, G. M.; Wood, G. J.; Paterson, J. L.
      British Journal of Anaesthesia (1984), 56 (8), 903-4CODEN: BJANAD; ISSN:0007-0912.
      The half-life of plasma cholinesterase (EC 3.1.1.8) was detd. by measurement of the rate of reappearance of enzyme activity after marked depletion assocd. with repeated plasma exchanges. Half-life values of 5.0 and 5.4 days were found in 2 patients.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaL2cXlsVyktr8%253D&md5=342f935c61f747f057735e5591f876aa
    36. 36
      Raveh, L.; Grauer, E.; Grunwald, J.; Cohen, E.; Ashani, Y. Toxicol. Appl. Pharmacol. 1997, 145, 43– 53 DOI: 10.1006/taap.1997.8160
      36
      The stoichiometry of protection against soman and VX toxicity in monkeys pretreated with human butyrylcholinesterase
      Raveh, Lily; Grauer, Ettie; Grunwald, Jacob; Cohen, E.; Ashani, Yacov
      Toxicology and Applied Pharmacology (1997), 145 (1), 43-53CODEN: TXAPA9; ISSN:0041-008X. (Academic)
      Bioscavengers of organophosphates (OP) have been examd. as potential substitutes for the currently approved drug treatment against OP toxicity. The present work was designed to assess the ability of butyrylcholinesterase, purified from human serum (HuBChE), to prevent the toxicity induced by soman and VX in rhesus monkeys. The consistency of the data across species was then evaluated as the basis for the extrapolation of the data to humans. The av. mean residence time of the enzyme in the circulation of monkeys following an i.v. loading was 34 h. High bioavailability of HuBChE in blood (>80%) was demonstrated after i.m. injection. A molar ratio of HuBChE:OP ∼1.2 protected against an i.v. bolus injection of 2.1 × LD50 VX, while a ratio of 0.62 was sufficient to protect monkeys against an i.v. dose of 3.3 × LD50 of soman, with no addnl. postexposure therapy. A remarkable protection was also seen against soman-induced behavioral deficits detected in the performance of a spatial discrimination task. The consistency of the results across several species offers a reliable prediction of both the stoichiometry of the scavenging and the extent of prophylaxis with HuBChE against nerve agent toxicity in humans.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXktl2htbg%253D&md5=05dff66162cebdd4cba95a1d51bc6325
    37. 37
      Raveh, L.; Grunwald, J.; Marcus, D.; Papier, Y.; Cohen, E.; Ashani, Y. Biochem. Pharmacol. 1993, 45, 2465– 2474 DOI: 10.1016/0006-2952(93)90228-O
      There is no corresponding record for this reference.
    38. 38
      Lenz, D. E.; Maxwell, D. M.; Koplovitz, I.; Clark, C. R.; Capacio, B. R.; Cerasoli, D. M.; Federko, J. M.; Luo, C.; Saxena, A.; Doctor, B. P. Chem.-Biol. Interact. 2005, 157, 205– 210 DOI: 10.1016/j.cbi.2005.10.025
      38
      Protection against soman or VX poisoning by human butyrylcholinesterase in guinea pigs and cynomolgus monkeys
      Lenz, David E.; Maxwell, Donald M.; Koplovitz, Irwin; Clark, Connie R.; Capacio, Benjamin R.; Cerasoli, Douglas M.; Federko, James M.; Luo, Chunyuan; Saxena, Ashima; Doctor, Bhupendra P.; Olson, Carl
      Chemico-Biological Interactions (2005), 157-158 (), 205-210CODEN: CBINA8; ISSN:0009-2797. (Elsevier Ireland Ltd.)
      Human butyrylcholinesterase (HuBuChE), purified from outdated human plasma, is being evaluated for efficacy against nerve agents in guinea pigs and cynomolgus monkeys. Previous studies in rodents and nonhuman primates demonstrated that pretreatment of animals with enzymes that can scavenge nerve agents could provide significant protection against behavioral and lethal effects of nerve agent intoxication. In prepn. for evaluation of efficacy of HuBuChE prior to initiating an investigational new drug (IND) application, the pharmacokinetics of HuBuChE were evaluated in guinea pigs and in cynomolgus monkeys. HuBuChE was injected i.m. at two doses, and blood samples were taken to follow the time-course of HuBuChE in blood for up to 168 h after administration. In guinea pigs, the two doses of HuBuChE, 19.9 and 32.5 mg/kg, produced similar times of maximal blood concn. (Tmax of 26.0 and 26.8 h, resp.) and similar elimination half-times (t1/2 of 64.6 and 75.5 h, resp.). Enzyme levels were still 10-fold over baseline at 72 h. Based on these data, guinea pigs were administered 150 mg/kg of enzyme i.m. and challenged at T max. Soman or VX doses were approx. 1.5, 2.0 and 2.0 × LD50 administered s.c. in sequence at 90-120 min apart. None of the animals displayed signs of organophosphorus (OP) anticholinesterase intoxication at any of the challenge levels, and all survived for the 14-day duration of the expt. Similar expts. were carried out with cynomolgus monkeys to det. the pharmacokinetics of HuBuChE and its efficacy against soman. The complete survival of nearly all animals tested to date, coupled with the maximal blood concn. and half-life elimination profile obtained for HuBuChE after i.m. injection, provides strong support for the continued development of HuBuChE as a product to protect against nerve agents.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXhtlShs7jM&md5=ff0b18498b651db8c6357fa3ea9a1c4c
    39. 39
      Black, R.; Clarke, R.; Harrison, J.; Read, R. Xenobiotica 1997, 27, 499– 512 DOI: 10.1080/004982597240460
      There is no corresponding record for this reference.
    40. 40
      Nakahara, Y. J. Chromatogr., Biomed. Appl. 1999, 733, 161– 180 DOI: 10.1016/S0378-4347(99)00059-6
      40
      Hair analysis for abused and therapeutic drugs
      Nakahara, Y.
      Journal of Chromatography B: Biomedical Sciences and Applications (1999), 733 (1 + 2), 161-180CODEN: JCBBEP; ISSN:0378-4347. (Elsevier Science B.V.)
      A review and discussion with 164 refs. which focuses on basic aspects and recent studies of hair anal. for abused and therapeutic drugs. Firstly, biol. of hair and sampling of hair specimens have been commented for the sake of correct interpretation of the results from hair anal. Then the usual washing methods of hair samples and the extn. methods for drugs in hair have been shown and commented on. Anal. methods for each drug have been discussed by the grouping of three anal. methods, namely immunoassay, HPLC-CE and GC-MS. The outcomes of hair anal. studies have been reviewed by dividing into six groups; morphine and related, cocaine and related, amphetamines, cannabinoids, the other abused drugs and therapeutic drugs. In addn., reports on stability of drugs in the living hair and studies on drug incorporation into hair and dose-hair concn. relationships have been reviewed. Applications of hair anal. to the estn. of drug history, discrimination between OTC drug use and illegal drug use, drug testing for acute poisoning, gestational drug exposure and drug compliance have also been reviewed. Finally, the promising prospects of hair anal. have been described.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1MXmvVKhtLc%253D&md5=81417dd85b3524b7b5a4d64918f521b3
    41. 41
      Hadidi, K. A.; Almasad, J. K.; Al-Nsour, T.; Abu-Ragheib, S. Forensic Sci. Int. 2003, 135, 129– 136 DOI: 10.1016/S0379-0738(03)00196-8
      41
      Determination of tramadol in hair using solid phase extraction and GC-MS
      Hadidi, Kamal A.; Almasad, Jamal K.; Al-Nsour, Thair; Abu-Ragheib, Samih
      Forensic Science International (2003), 135 (2), 129-136CODEN: FSINDR; ISSN:0379-0738. (Elsevier Science Ltd.)
      Tramadol is a centrally acting synthetic analgesic with μ-opioid receptor agonist activity, it is a widely prescribed analgesic used in the treatment of moderate to severe pain and as an alternative to opiates. Tramadol causes less respiratory depression than morphine at recommended doses. Its efficacy and low incidence of side effects lead to its unnecessary prescribing in patients with mild pain. Tramadol was classified as a "controlled drug" long after its approval for use in Jordan. Anal. of drugs of abuse in hair has been used in routine forensic toxicol. as an alternative to blood in studying addiction history of drug abusers. A method for the detn. of tramadol in hair using solid phase extn. and gas chromatog.-mass spectrometry (GC-MS) is presented, the method offers excellent precision (3.5-9.8%, (M)=6.77%), accuracy (6.9-12%, M=9.4%) and limit of detection 0.5 ng/mg. The recovery was in the range of 87-94.3% with an av. of 90.75%. The calibration curve was linear over the concn. range 0.5-5.0 ng/mg hair with correlation coeff. of 0.998. The developed method was tested on 11 hair samples taken from patients using tramadol as prescribed by their physician along with other different drugs in treating chronic illnesses. Tramadol was detected in all hair samples at a concn. of 0.176-16.3 ng/mg with mean concn. of 4.41 ng/mg. The developed method has the potential of being applied in forensic drug hair testing. In Jordan, hair drug testing started to draw the attention of legal authorities which stimulated forensic toxicologists in recent years to develop methods of anal. of drugs known or have the potential to be abused.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXmt1ensb8%253D&md5=98eca8ae3a404acc7685a7cb5b5d6c67
    42. 42
      Boumba, V.; Ziavrou, K.; Vougiouklakis, T. Int. J. Toxicol. 2006, 25, 143– 163 DOI: 10.1080/10915810600683028
      42
      Hair as a biological indicator of drug use, drug abuse or chronic exposure to environmental toxicants
      Boumba, Vassiliki A.; Ziavrou, Kallirroe S.; Vougiouklakis, Theodore
      International Journal of Toxicology (2006), 25 (3), 143-163CODEN: IJTOFN; ISSN:1091-5818. (Taylor & Francis, Inc.)
      A review. In recent years hair has become a fundamental biol. specimen, alternative to the usual samples blood and urine, for drug testing in the fields of forensic toxicol., clin. toxicol. and clin. chem. Moreover, hair-testing is now extensively used in workplace testing, as well as, on legal cases, historical research etc. This article reviews methodol. and practical issues related to the application of hair as a biol. indicator of drug use/abuse or of chronic exposure to environmental toxicants. Hair structure and the mechanisms of drug incorporation into it are commented. The usual prepn. and extn. methods as well as the anal. techniques of hair samples are presented and commented on. The outcomes of hair anal. have been reviewed for the following categories: drugs of abuse (opiates, cocaine and related, amphetamines, cannabinoids), benzodiazepines, prescribed drugs, pesticides and org. pollutants, doping agents and other drugs or substances. Finally, the specific purpose of the hair testing is discussed along with the interpretation of hair anal. results regarding the limitations of the applied procedures.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD28XntFelsro%253D&md5=003f69589b4497e8e0a8709daffe04b8
    43. 43
      Moore, C.; Guzaldo, F.; Donahue, T. J. Anal. Toxicol. 2001, 25, 555– 558 DOI: 10.1093/jat/25.7.555
      43
      The determination of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in hair using negative ion gas chromatography-mass spectrometry and high-volume injection
      Moore, Christine; Guzaldo, Frank; Donahue, Thomas
      Journal of Analytical Toxicology (2001), 25 (7), 555-558CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
      The detn. of 11-nor-Δ9-THC-9-carboxylic acid (THC-COOH) in hair specimens at the sensitivity required to detect marijuana users is a difficult anal. problem. A sensitive and specific method has been developed for the quant. assay of THC-COOH in hair. Hair specimens were washed, incubated in sodium hydroxide, subjected to solid-phase extn., and analyzed using high-vol. injection coupled with neg. chem. ionization (NCI) mass spectrometry. A common disadvantage of chem. ionization, the prodn. of a single mass-to-charge ratio ion, was also addressed. By specific selection of the derivatizing agent, three ions were monitored, allowing the calcn. of two ion ratios, as in electron impact mode. The method was applied to several hair specimens taken from known marijuana users and workplace specimens. This is the first publication describing the use of high-vol. injection and NCI mass spectrometry for the detn. of THC-COOH in hair. (c) 2001 Preston Publications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3MXnsVCgsr8%253D&md5=3b992d265d933780449033eae93d7bfc
    44. 44
      Phinney, K. W.; Sander, L. C. Anal. Bioanal. Chem. 2004, 378, 144– 149 DOI: 10.1007/s00216-003-2366-3
      44
      Liquid chromatographic method for the determination of enantiomeric composition of amphetamine and methamphetamine in hair samples
      Phinney, Karen W.; Sander, Lane C.
      Analytical and Bioanalytical Chemistry (2004), 378 (1), 144-149CODEN: ABCNBP; ISSN:1618-2642. (Springer-Verlag)
      Interest in hair anal. as an alternative or complementary approach to urinalysis for drug abuse detection has grown in recent years. Hair anal. can be particularly advantageous for drugs such as amphetamine and methamphetamine that are rapidly excreted. Confirmation of abuse of these stimulants is complicated by the fact that some forms are found in legitimate medications. Examn. of the enantiomeric compn. of amphetamine and methamphetamine in hair samples can provide valuable assistance in interpreting drug testing results. The authors developed a liq. chromatog. for the sepn. of amphetamine and methamphetamine enantiomers isolated from human hair samples. The drug enantiomers were sepd. on a chiral stationary phase after derivatization with an achiral fluorescent agent. The methodol. was evaluated with a Std. Ref. that contained several drugs of abuse including amphetamine and methamphetamine.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXps1yjtbk%253D&md5=1d2f82f49de102b6b7fd2c5fb16da156
    45. 45
      Romolo, F. S.; Rotolo, M. C.; Palmi, I.; Pacifici, R.; Lopez, A. Forensic Sci. Int. 2003, 138, 17– 26 DOI: 10.1016/j.forsciint.2003.07.013
      45
      Optimized conditions for simultaneous determination of opiates, cocaine and benzoylecgonine in hair samples by GC-MS
      Romolo, F. S.; Rotolo, M. C.; Palmi, I.; Pacifici, R.; Lopez, A.
      Forensic Science International (2003), 138 (1-3), 17-26CODEN: FSINDR; ISSN:0379-0738. (Elsevier Science Ltd.)
      The present paper describes a qual. and quant. method for the simultaneous detection of opiates, cocaine and benzoylecgonine from human hair samples. Every step of the anal. procedure was studied to find the optimized conditions. Nine different incubation systems were examd. The influence of different pH values of samples on the isolation of analytes from the incubation media by Bond Elut cartridges and the stability of the compds. of interest in the different incubation media and conditions were investigated. The extg. power of different incubation media was studied as well. The phosphate buffer 0.1N at pH 5 was chosen as the extn. medium in an optimized procedure for simultaneous detn. of opiates, cocaine and benzoylecgonine in hair samples. The method developed was validated. Recoveries were 90% for morphine (M), 81% for 6-monoacetylmorphine (6-AM), 90% for codeine (CD), 86% for cocaine (C) and 90% for benzoylecgonine (BE). Relative std. deviation for inter-day precision was better than 12%. The limits of detection resulted as 0.05 ng/mg for M and C, as 0.08 for 6-AM and as 0.2 ng/mg for BE. Forty hair samples collected from drug abusers admitted to centers for detoxification treatment were analyzed obtaining 23 pos. results for opiates and/or cocaine. Twelve hair specimens longer than 10 cm were analyzed following a sectional approach. In the six pos. cases, it was interesting to find that the 6-AM/M ratio generally decreased for each sample from the proximal segment to the distal segments. Moreover, the 6-AM/M ratio was generally lower than 1 in the intermediate and distal segments.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXpt1WitL4%253D&md5=562c0571386f6de1d8d2a5015636d777
    46. 46
      Scheidweiler, K. B.; Huestis, M. A. Anal. Chem. 2004, 76, 4358– 4363 DOI: 10.1021/ac049555t
      There is no corresponding record for this reference.
    47. 47
      Brewer, W. E.; Galipo, R. C.; Sellers, K. W.; Morgan, S. L. Anal. Chem. 2001, 73, 2371– 2376 DOI: 10.1021/ac000871r
      There is no corresponding record for this reference.
    48. 48
      Wada, M.; Nakashima, K. Anal. Bioanal. Chem. 2006, 385, 413– 415 DOI: 10.1007/s00216-006-0332-6
      48
      Hair analysis: an excellent tool for confirmation of drug abuse
      Wada, Mitsuhiro; Nakashima, Kenichiro
      Analytical and Bioanalytical Chemistry (2006), 385 (3), 413-415CODEN: ABCNBP; ISSN:1618-2642. (Springer)
      A review of methods for hair anal. forensic toxicol. and drug abuse studies.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD28XkvVWlt7o%253D&md5=6bebaf84f67a9cf2a400d95fe1d66523
    49. 49
      Kintz, P.; Cirimele, V.; Jamey, C.; Ludes, B. J. Forensic Sci. 2003, 48, 195– 200 DOI: 10.1520/JFS2002209
      49
      Testing for GHB in hair by GC/MS/MS after a single exposure. Application to document sexual assault
      Kintz, Pascal; Cirimele, Vincent; Jamey, Carole; Ludes, Bertrand
      Journal of Forensic Sciences (2003), 48 (1), 195-200CODEN: JFSCAS; ISSN:0022-1198. (American Society for Testing and Materials)
      Gamma-hydroxybutyric acid, or GHB, is a substance naturally present within mammal species. Properties of neurotransmitter or neuromodulator are generally given to this substance. GHB is therapeutically used as an anesthetic, but can be used for criminal offenses (date-rape drug). It appears that the window of detection of GHB is very short in both blood and urine, and therefore its presence is very difficult to prove after a rape case. In order to document single exposure, we investigated the use of hair. Hair was collected one month after the allegated event in order to sample the corresponding period after regular growing. After rapid (2 min) decontamination with dichloromethane, the hair shaft was cut into 3-mm segments. They were overnight incubated in 0.01 N NaOH in the presence of GHB-d6, followed by neutralization and extn. in Et acetate under acidic conditions. GHB (precursor ion m/z 233, productions m/z 147 and 148) was tested by GC/MS/MS (Finnigan TSQ 700) after derivatization with BSTFA + 1% TMCS. Physiol. concns. (n = 24) were in the range 0.5 to 12.0 ng/mg, with no influence due to hair color. No variation of concns. was obsd. along the hair shaft in controlled subjects, except for the proximal segment, due to an incorporation through sweat. This demonstrates that endogenous levels for each single subject are const. during hair growth. A controlled human administration of 25 mg/kg to a volunteer demonstrated that a single exposure to GHB is detectable in hair after segmentation. In a case of rape under influence, a clear increase of the corresponding segment (about 2.4 ng/mg) in time was obsd., in comparison with the other segments (0.6 to 0.8 ng/mg). This study demonstrates that a single exposure to GHB in a case of sexual assault can be documented by hair anal. when collected about one month after the crime.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXhtVSntL8%253D&md5=be588da0f61623cdee2947f9fe6c4db8
    50. 50
      Negrusz, A.; Moore, C. M.; Hinkel, K. B.; Stockham, T. L.; Verma, M.; Strong, M. J.; Janicak, P. G. J. Forensic Sci. 2001, 46, 1143– 1151 DOI: 10.1520/JFS15113J
      50
      Deposition of 7-aminoflunitrazepam and flunitrazepam in hair after a single dose of Rohypnol
      Negrusz, Adam; Moore, Christine M.; Hinkel, Karley B.; Stockham, Teri L.; Verma, Mauli; Strong, Mary Jane; Janicak, Philip G.
      Journal of Forensic Sciences (2001), 46 (5), 1143-1151CODEN: JFSCAS; ISSN:0022-1198. (American Society for Testing and Materials)
      In recent years, there has been a notable increase in the no. of reports on drug-facilitated sexual assault. Benzodiazepines are the most common so-called "date-rape" drugs, with flunitrazepam (Rohypnol) being one of the most frequently mentioned. The aim of this study was to det. whether flunitrazepam and its major metabolite 7-aminoflunitrazepam could be detected in hair collected from ten healthy volunteers after receiving a single 2 mg dose of Rohypnol using solid phase extn. and NCI-GC-MS. Such data would be of great importance to law enforcement agencies trying to det. the best time interval for hair collection from a victim of drug-facilitated sexual assault in order to reveal drug use. Ten healthy volunteers (eight women and two men, 21 to 49 yr old) participated in the study. The following hair samples were collected from each volunteer: one before flunitrazepam administration, and 1, 3, 5, 14, 21, and 28 days after. In five volunteers, 7-aminoflunitrazepam was detected 24 h after flunitrazepam administration and remained in hair throughout the entire 28-day study period (0.6-8.0 pg/mg). In two cases, 7-aminoflunitrazepam appeared in hair 21 days after drug intake (0.5-2.7 pg/mg), and in two subjects 14 days later (0.5-5.4 pg/mg). In one volunteer, 7-aminoflunitrazepam was detected on day 14 and 21 but concns. were below the quantitation limit. Flunitrazepam was detected in some samples but all concns. were below the quantitation limit (0.5-2.3 pg/mg).
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3MXntFGksL8%253D&md5=b70004c248b45a54db8cdf5b5f8ae41a
    51. 51
      Goulle, J. P.; Cheze, M.; Pepin, G. J. Anal. Toxicol. 2003, 27, 574– 580 DOI: 10.1093/jat/27.8.574
      51
      Determination of Endogenous Levels of GHB in Human Hair. Are there Possibilities for the Identification of GHB Administration through Hair Analysis in Cases of Drug-Facilitated Sexual Assault?
      Goulle, Jean Pierre; Cheze, Marjorie; Pepin, Gilbert
      Journal of Analytical Toxicology (2003), 27 (8), 574-580CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
      The authors have developed a GC-MS-MS assay for GHB in human hair. 5 Mg of washed hair were hydrolyzed by 1M or 0.01M NaOH before a liq.-liq. extn. with Et acetate under acidic conditions. GHB-d6 was used as the internal std. TMS derivs. were formed before injection. TBDMS derivs. were used in cases of strong chromatog. interferences or in a confirmatory procedure. Anal. of basal levels of GHB in 61 drug-free donors gave the following results: the mean measured concn. for blond hair was 0.60 ng/mg (n = 12), SD = 0.19 ng/mg, and extreme figures were in the range 0.35-0.95 ng/mg. For brown hair, the mean measured concn. was 0.90 ng/mg (n = 30), SD = 0.42 ng/mg, and extreme figures 0.41-1.86 ng/mg. For black hair, the mean measured concn. was 0.90 ng/mg (n = 19), SD = 0.37 ng/mg, and extreme figures 0.32-1.54 ng/mg, showing no significant differences depending on hair color. Anal. of basal levels of GHB of 12 or more specimens in segmented hair showed a mean concn. of 1.22 ng/mg (0.31-8.4 ng/mg) and a relative std. deviation for each individual ranging from 6.75% to 37.98%. GHB was administered to a healthy 53-yr-old white male (light brown hair) at oral dosages of 30, 45, and 60 mg/kg. Beard hair was collected just before administration and 24 h after (and each day for one week for the last dose), and a 7.5-cm scalp hair lock was collected 7 days after the last dose. A rise in GHB concn. was obsd. in beard hair for the 45 and 60 mg/kg dosages with a max. at 24 h, whereas no change was obsd. for the 30 mg/kg dosage. Scalp hair was segmented into 3-mm long segments. The 3 proximal last segments showed significantly (0.0005 < p < 0.005) different concns. of GHB (1.22, 1.27, and 1.66 ng/mg, resp.) when compared with the basal physiol. level of GHB in this same person (mean = 0.62 ng/mg, SD = 0.15 ng/mg). A case of daily GHB abuse during bodybuilding allowed us to det. a concn. of GHB of 14 ng/mg, in a 2-cm long segment (black hair). A case of rape under the influence of GHB was documented through hair anal. (black hair) and pos. anal. of the glass she used. Sampled 7 days after the sexual assault, the 3 last 3-mm long proximal segments tested for GHB exhibited concns. of 3.1-5.3 and 4.3 ng/mg, resp., whereas the mean physiol. level detd. in this woman was 0.71 ng/mg, SD = 0.17 ng/mg. The authors advise a 2 -step hair sampling as evidence of GHB consumption: the 1st sample at the time of exposure to show the contamination by sweat of the proximal segment in case of recent administration with a significant rise of hair level at the root, and the second after at least 3 or 4 wk to avoid this contamination and det. the levels incorporated in the hair matrix before, during, and after the exposure. (c) 2003 Preston Publications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXoslOju70%253D&md5=bc63502f405ebc734b70e82bf31aa44a
    52. 52
      Frison, G.; Favretto, D.; Tedeschi, L.; Ferrara, S. D. Forensic Sci. Int. 2003, 133, 171– 174 DOI: 10.1016/S0379-0738(03)00064-1
      52
      Detection of thiopental and pentobarbital in head and pubic hair in a case of drug-facilitated sexual assault
      Frison, Giampietro; Favretto, Donata; Tedeschi, Luciano; Ferrara, Santo Davide
      Forensic Science International (2003), 133 (1-2), 171-174CODEN: FSINDR; ISSN:0379-0738. (Elsevier Science Ireland Ltd.)
      The quali-quant. detn. of 2 barbiturates, thiopental and its metabolite pentobarbital, in head and pubic hair samples of a woman who had been sexually assaulted during hospitalization, is reported. Hair was analyzed by means of solid-phase microextn. (SPME) and gas chromatog.-multiple mass spectrometry (GC-MS-MS), in chem.-ionization conditions. Thiopental and pentobarbital were found in 3 proximal head hair segments (sample 1A: 0.30 and 0.40 ng/mg; sample 1B: 0.20 and 0.20 ng/mg; sample 3: 0.15 and 0.20 ng/mg) and pubic hair sample. Two distal head hair segments were neg. for both barbiturates. Despite the lack of collection and toxicol. anal. of blood or urine samples within the hospital setting, anal. findings from hair revealed the use of the anesthetic agent thiopental to sedate the victim quickly and deeply and commit sexual assault.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXjs1aiu78%253D&md5=f10b965ff10eebc034920c162fe28c02
    53. 53
      Negrusz, A.; Moore, C. M.; Kern, J. L.; Janicak, P. G.; Strong, M. J.; Levy, N. A. J. Anal. Toxicol. 2000, 24, 614– 620 DOI: 10.1093/jat/24.7.614
      53
      Quantitation of clonazepam and its major metabolite 7-aminoclonazepam in hair
      Negrusz, Adam; Moore, Christine M.; Kern, Jennifer L.; Janicak, Philip G.; Strong, Mary Jane; Levy, Naomi A.
      Journal of Analytical Toxicology (2000), 24 (7), 614-620CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
      As with some other benzodiazepines, clonazepam (CLO) is a drug possibly used in "date-rape" situations. A method using solid-phase extn. followed by a highly sensitive neg. chem. ionization gas chromatog.-mass spectrometry procedure was developed for the simultaneous quantitation of CLO and its major metabolite, 7-aminoclonazepam (7-ACLO), in hair. The method has potential application to alleged drug-facilitated rape cases. To det. the feasibility of detecting 7-ACLO and CLO in hair, specimens were collected from psychiatric patients treated with CLO, divided into 2-cm segments, and analyzed. Std. curves for 7-ACLO (1-1000 pg/mg) and CLO (10-400 pg/mg) had correlation coeffs. of 0.998. All precision and accuracy values were within acceptable limits. 7-ACLO was present in measurable quantities (1.37-1267 pg/mg) in 9 of 10 patient samples. CLO concns. in hair were much lower (10.7-180 pg/mg). In 4 of 10 cases, CLO was not detected in hair. Two patients who had never before been treated with CLO received a single 2-mg dose of the drug. Approx. 3 wk later, hair samples were collected, and measurable quantities of 7-ACLO (4.8 pg/mg) were detected in the 1st segment (proximal) of one of those samples, and traces of the drug were present in the other sample. It is concluded that 7-ACLO is deposited in hair in much higher quantities than the parent drug and remains there for extended periods of time. The study also indicates that it is possible to detect 7-ACLO after a single dose of CLO, as in the typical date-rape scenarios. (c) 2000 Preston Publications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3cXntlOltr4%253D&md5=6a4b6131af7874534652eb1cac027253
    54. 54
      Covaci, A.; Tutudaki, M.; Tsatsakis, A. M.; Schepens, P. Chemosphere 2002, 46, 413– 418 DOI: 10.1016/S0045-6535(01)00065-0
      There is no corresponding record for this reference.
    55. 55
      Zhang, H.; Chai, Z.; Sun, H. Environ. Int. 2007, 33, 685– 693 DOI: 10.1016/j.envint.2007.02.003
      There is no corresponding record for this reference.
    56. 56
      Margariti, M. G.; Tsatsakis, A. M. Biomarkers 2009, 14, 137– 147 DOI: 10.1080/13547500902792912
      There is no corresponding record for this reference.
    57. 57
      Tsatsakis, A. M.; Tutudaki, M.; Tzatzarakis, M. N.; Dawson, A.; Mohamed, F.; Christaki, M.; Alegakis, A. K. Hum. Exp. Toxicol. 2012, 31, 266– 273 DOI: 10.1177/0960327111403171
      57
      Is hair analysis for dialkyl phosphate metabolites a suitable biomarker for assessing past acute exposure to organophosphate pesticides?
      Tsatsakis, A. M.; Tutudaki, M.; Tzatzarakis, M. N.; Dawson, A.; Mohamed, F.; Christaki, M.; Alegakis, A. K.
      Human & Experimental Toxicology (2012), 31 (3), 266-273CODEN: HETOEA; ISSN:0960-3271. (Sage Publications Ltd.)
      In the present paper, the possibility to use dialkyl phosphate metabolites (DAPs) hair segmental anal. as a biomarker of past acute exposure to organophosphates is examd. Hair samples of four acute poisoning survivors were collected and segmental hair anal. was performed. The total hair samples were divided to 1 cm segments and analyzed by gas chromatog.-mass spectrometry (GC-MS) for the presence of four DAP metabolites, di-Me phosphate (DMP), di-Et phosphate (DEP), di-Et thiophosphate (DETP) and di-Et dithiophosphate (DEDTP). Results were examd. under the light of pesticide type and time of hair sample collection. Although DAPs were detected all along the hair shaft, higher concns. (peaks) were detected in the segments proximate to the suicide period. It was also obsd. that the elevated concns. of the present metabolites corresponded to the ones produced by the ingested parent compd. Conclusively, measurements of DAPs in the appropriate hair segments of OP-poisoned patients can be used for assessing past acute exposure to organophosphates in certain cases.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xot1ygu74%253D&md5=a0587da5a4980c50f741e4ba9c83160f
    58. 58
      Tsatsakis, A. M.; Tzatzarakis, M. N.; Tutudaki, M.; Babatsikou, F.; Alegakis, A. K.; Koutis, C. Hum. Exp. Toxicol. 2008, 27, 933– 940 DOI: 10.1177/0960327108102047
      58
      Assessment of levels of organochlorine pesticides and their metabolites in the hair of a Greek rural human population
      Tsatsakis, A. M.; Tzatzarakis, M. N.; Tutudaki, M.; Babatsikou, F.; Alegakis, A. K.; Koutis, C.
      Human & Experimental Toxicology (2008), 27 (12), 933-940CODEN: HETOEA; ISSN:0960-3271. (Sage Publications Ltd.)
      We present the assessment of chronic exposure of the rural population of Helia Peloponnesus, Greece to banned organochlorine pesticides, hexachlorocyclohexane (HCH), and 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT), using hair anal. A total of 222 head hair samples were collected and analyzed for the presence of those organochlorine pesticides and their metabolites or isomers. Gas chromatog. coupled to mass spectrometry was used to measure the levels of the pollutants. The median concns. of α-HCH, hexachlorobenzene, lindane, ortho para 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (opDDE), para para 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (ppDDE), ortho para 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (opDDD), para para 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (ppDDD) + ortho para 1,1,1-trichloro-2,2-bis(4-chlorophenyl)-ethane, and para para 1,1,1-trichloro-2,2-bis(4-chloro-phenyl)-ethane were detd. at 40.4, 19.7, 124.2, 6.2, 7.8, 73.1, 8.0, and 5.7 pg/mg. The median concn. of total HCHs and DDTs were 117.8 pg/mg and 9.4 pg/mg, resp. The levels of total HCHs were much higher than the levels of DDTs in the hair samples of the studied population. This may be attributed to the presence of lindane, a pesticide officially banned in 2002. It is interesting to see that DDTs are still traced in samples despite their use being banned for more than three decades. There was no difference in the levels of the detected pesticides in hair sampled from men or women. The concn. of HCHs remains high and relatively stable across the age groups, suggesting const. exposure until very recently. The concn. of the total DDTs and the parent compd., pp-DDT presents a statistically significant decreasing trend across the age groups.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXltVOgsbg%253D&md5=2d427cbc71019db9810fc22ae7be3e5a
    59. 59
      Smith-Baker, C.; Saleh, M. A. J. Environ. Sci. Health, Part B 2011, 46, 648– 653 DOI: 10.1080/03601234.2012.597701
      There is no corresponding record for this reference.
    60. 60
      Tsatsakis, A. M.; Tutudaki, M. I.; Tzatzarakis, M. N.; Psaroudakis, K.; Dolapsakis, G. P.; Michalodimitrakis, M. N. Vet. Hum. Toxicol. 1998, 40, 200– 203
      60
      Pesticide deposition in hair: preliminary results of a model study of methomyl incorporation into rabbit hair
      Tsatsakis, A. M.; Tutudaki, M. I.; Tzatzarakis, M. N.; Psaroudakis, K.; Dolapsakis, G. P.; Michalodimitrakis, M. N.
      Veterinary and Human Toxicology (1998), 40 (4), 200-203CODEN: VHTODE; ISSN:0145-6296. (Comparative Toxicology Laboratories, Kansas State University)
      This work studied the incorporation of methomyl, a carbamate insecticide, into the hair of New Zealand white rabbits. A total of 600 mg methomyl was administered by drinking water over 4 mo, and acetyl-cholinesterase activity in serum was monitored. At the end of the dosing period, hair from the back of the rabbits was cut off, and the methomyl concn. was measured using ELISA and HPLC. A decrease of serum acetylcholinesterase occurred. The top cm of hair contained no methomyl, the second cm contained 0.9 ng/mg and the 3rd cm of hair contained 3 ng methomyl/mg. Methomyl was incorporated into the rabbit hair in a process independent of gender but dependent on the hair growth rate.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXltFSmsbo%253D&md5=936cc70a42ebcb08294407d1f388276a
    61. 61
      Tutudaki, M.; Tsakalof, A. K.; Tsatsakis, A. M. Hum. Exp. Toxicol. 2003, 22, 159– 164 DOI: 10.1191/0960327103ht334oa
      61
      Hair analysis used to assess chronic exposure to the organophosphate diazinon: A model study with rabbits
      Tutudaki, Maria; Tsakalof, Andreas K.; Tsatsakis, Aristidis M.
      Human & Experimental Toxicology (2003), 22 (3), 159-164CODEN: HETOEA; ISSN:0960-3271. (Arnold, Hodder Headline)
      The main purpose of the present study was to det. whether hair anal. would be a suitable method to assess chronic exposure of rabbits to the pesticide diazinon. A controlled study was designed, in which white rabbits of the New Zealand variety were systemically exposed to two dosage levels (15 mg/kg per day and 8 mg/kg per day) of the pesticide, through their drinking water, for a period of 4 mo. Hair samples from the back of the rabbits were removed before commencing the expt. and at the end of the dosing period. Parallel expts. with spiked hair were carried out in order to design a simple and efficient method of extn. of diazinon from hair. The hair was pulverized in a ball mill homogenizer, incubated in methanol at 37°C overnight, liq.-liq. extd. with Et acetate and measured by chromatog. techniques (GC-NPD and GC-MS) for confirmation. The concn. of the diazinon in the hair of the exposed animals ranged from 0.11 to 0.26 ng/mg hair. It was concluded that there is a relationship between the administered dose and the detected pesticide concn. in hair. Finally, it seems that hair anal. may be used to investigate chronic exposure to the pesticide.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXjslCru7g%253D&md5=622e25095a2c2b6a19abebd9bacfd8ed
    62. 62
      Tutudaki, M.; Tsatsakis, A. M. J. Anal. Toxicol. 2005, 29, 805– 809 DOI: 10.1093/jat/29.8.805
      62
      Pesticide Hair Analysis: Development of a GC-NCI-MS Method to Assess Chronic Exposure to Diazinon in Rats
      Tutudaki, Maria; Tsatsakis, Aristidis M.
      Journal of Analytical Toxicology (2005), 29 (8), 805-809CODEN: JATOD3; ISSN:0146-4760. (Preston Publications)
      The present study aimed to improve the gas chromatog.-mass spectrometry (GC-MS) method, already developed in our lab., for trace anal. of diazinon in hair. Furthermore, it aimed to compare the disposition of the pesticide in the hair of 2 different animal species, one susceptible to diazinon toxicity and one resistant, under identical exptl. conditions. Sprague Dawley rats were systemically exposed to 2 dose levels (6 mg/kg/day and 3 mg/kg/day) of the pesticide, through their drinking water, for a period of one and a half months. Hair samples from the back of the rats were removed before commencing the expt. and at the end of the dosing period. Diazinon was selectively isolated from pulverized hair, sample or spiked, by stepwise consequent extns. with methanol and Et acetate and quantified by GC-neg. chem. ionization-MS. It was found that the concn. of diazinon in the hair of exposed animals was dose dependent and was found to be 0.24 ± 0.01 ng/mg (n = 5) and 0.53 ± 0.05 ng/mg (n = 5) for the low and high dosage, resp. The concn. in both dose groups was much higher than the corresponding rabbit hair (rabbits were exposed to the pesticide under similar exptl. conditions) as previously reported. These results strongly point to the possibility of using hair anal. for low-level exposure monitoring of diazinon. (c) 2005 Preston Publications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2MXht1CqsLnI&md5=2c49bd68e7747008c122a6e1462c373f
    63. 63
      Shih, M.; Smith, J.; McMonagle, J.; Dolzine, T.; Gresham, V. Biol. Mass Spectrom. 1991, 20, 717– 723 DOI: 10.1002/bms.1200201111
      63
      Detection of metabolites of toxic alkyl methylphosphonates in biological samples
      Shih, M. L.; Smith, J. R.; McMonagle, J. D.; Dolzine, T. W.; Gresham, V. C.
      Biological Mass Spectrometry (1991), 20 (11), 717-23CODEN: BIMSEH; ISSN:1052-9306.
      The major metabolites and breakdown products of some toxic organophosphonates are their resp. alkyl methylphosphonic acids. These acids ionize at physiol. pH and are not amenable to gas chromatog. anal. in their underivatized forms. Their detection in biol. samples has been difficult because of their presence at only trace levels. Existing anal. methods were developed mainly for measuring these phosphonic acids in environmental samples and at higher concns. In this study, a gas chromatog./mass spectrometric method was devised to provide confirmation and quantification of the organophosphonic acids of soman (GD), sarin (GB) and GF in blood and urine. This report describes the various derivatization conditions that we have studied and demonstrates the characteristic mass spectra by different ionization techniques.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK38Xhs1Onsw%253D%253D&md5=ce52adead6ff23189c60960171b1b93b
    64. 64
      Jakubowski, E.; Heykamp, L.; Durst, H.; Thomson, S. Anal. Lett. 2001, 34, 727– 737 DOI: 10.1081/AL-100103215
      64
      Preliminary studies in the formation of ethyl methylphosphonofluoridate from rat and human serum exposed to VX and treated with fluoride ion
      Jakubowski, E. M.; Heykamp, L. S.; Durst, H. D.; Thomson, S. A.
      Analytical Letters (2001), 34 (5), 727-737CODEN: ANALBP; ISSN:0003-2719. (Marcel Dekker, Inc.)
      A method has been developed for the anal. of a VX nerve agent biomarker in blood that is very sensitive, selective and within the capabilities of modern field mobile labs. A VX biomarker was found in spiked human and rat sera after treatment with fluoride ion and acetate buffer. VX was detected by the generation of its corresponding G-series deriv., Et methylphosphonofluoridate (VX-G). This method utilizes a C18 solid-phase extn. (SPE) followed by quantification using a gas chromatograph with either a flame photometric detector (GC-FPD) or a mass spectrometer (GC-MS). Samples are concd. by injecting 40-400 μL of ext. on a Tenax-TA sorbent tube along with 100 pg of decadeuterated di-Et Et phosphonate as the internal std. followed by thermal desorption GC-FPD anal. and GC-MS confirmation. VX-G was completely resolved from sarin (GB) and the method has the potential to resolve other nerve agents in the VX series of cholinesterase inhibitors. The method detection limit was 10.5 pg of agent on column. Quality control samples were analyzed and yielded spike recoveries greater than 95%.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3MXksVOitb0%253D&md5=c184165c9472a3114e6f7311632fbd1c
    65. 65
      Guide for the Care and Use of Laboratory Animals, 8th ed.; National Academies Press: Washington, DC, 2011.
      There is no corresponding record for this reference.
    66. 66
      Kalakuntla, R. R.; Kumar, K. S. J. Pharm. Sci. Res. 2009, 3, 1– 10
      There is no corresponding record for this reference.
    67. 67
      Loconto, P. R. Trace Environmental Quantitative Analysis Principles, Technique, and Application; CRC Press: Boca Raton, FL, 2006.
      There is no corresponding record for this reference.
    68. 68
      Wang, Q.; Xie, J.; Gu, M.; Feng, J.; Ruan, J. Chromatographia 2005, 62, 167– 173 DOI: 10.1365/s10337-005-0600-1
      There is no corresponding record for this reference.
    69. 69
      Hayes, T.; Kenny, D.; Hernon-Kenny, L. J. Med. Chem. Def. 2004, 2, 1– 23
      There is no corresponding record for this reference.
    70. 70
      Katagi, M.; Nishikawa, M.; Tatsuno, M.; Tsuchiahashi, H. J. Chromatogr., Biomed. Appl. 1997, 698, 81– 88 DOI: 10.1016/S0378-4347(97)00284-3
      70
      Determination of the main hydrolysis products of organophosphorus nerve agents, methylphosphonic acids, in human serum by indirect photometric detection ion chromatography
      Katagi, M.; Nishikawa, M.; Tatsuno, M.; Tsuchihashi, H.
      Journal of Chromatography B: Biomedical Sciences and Applications (1997), 698 (1 + 2), 81-88CODEN: JCBBEP; ISSN:0378-4347. (Elsevier)
      For the verification of the use of chem. warfare agents (CWA), sarin, soman and VX, a simple rapid and accurate method which allows us to simultaneously det. their degrdn. products, iso-Pr methylphosphonic acid (IPMPA), pinacolyl methylphosphonic acid (PMPA), Et methylphosphonic acid (EMPA) and methylphosphonic acid (MPA), in human serum, was explored by indirect photometric detection ion chromatog. (IPD-IC) which employs an anion-exchange column. IC anal. was performed after sample prepn. with an Ag+-form cation-exchange resin cartridge, and the four methylphosphonic acids could be sepd. well. The proposed conditions are as follows: eluent, 0.5 mM phthalic acid-0.1 mM Tris (hydroxymethyl) aminomethane-5% acetonitrile; flow-rate, 1.0 mL/min; temp., 50°; UV detector, 266 nm. All four methylphosphonic acids were eluted within 30 min with hardly any disturbance by impurities in the serum. Linear calibration curves were obtained for MPA, EMPA and IPMPA in the concn. range from 50 ng/mL to 1 μg/mL and for PMPA from 100 ng/mL to 1 μg/mL. The relative std. deviation for the methylphosphonic acids ranged from 3.8 to 6.9% at 500 ng/mL and the detection limits were 40 ng/mL for MPA, EMPA and IPMPA and 80 ng/mL for PMPA. The method would be suitable for anal. of human serum samples.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXlslemtr4%253D&md5=ceee5ba8cd1db960546d8e7705c7b32e