Take generous portions of analytical techniques, biotechnology, nanotechnology, and antiterrorism devices, and place into one extra-large convention center. Mix well.

“The Industrial Analytical Chemist in a Changing Scene.” “Recent Developments in Infrared Spectrometry.” “Some Unusual Cases in Photometric Analysis.” If you guessed that these were Pittcon tech-session titles, you’re right, but the year was 1950, Pittcon was actually in Pittsburgh, and the whole thing fit into the 17th floor of the William Penn Hotel. The factories, foundries, mines, and smelters of postwar Pittsburgh were running full throttle, and they all had testing and analysis laboratories. The time was ripe for the first Pittsburgh Conference. Fourteen exhibitors displayed their instruments in 25 booths, and 56 technical papers were presented. The 800 registered attendees paid $2 to register ($1 if they were students).

Fast-forward 52 years. Pittcon 2002 is the end of a three-year run at the gargantuan Morial Conference Center in New Orleans. More than 22,000 registered attendees (paying anywhere from $20 to $130 each) had nearly 1200 vendor exhibit booths, more than 1400 technical presentations, and more than 1000 posters to choose from, not to mention workshops, information exchanges, and press conferences.

Allen J. Bard of the University of Texas–Austin opened the conference with his plenary lecture, “The Fall and Rise of Analytical Chemistry in the 20th Century—What’s Next?” He outlined the new principles, theories, and technologies that “push” progress, as well as the new problems and regulatory demands that “pull” progress. The next five days featured an eclectic gumbo of symposia and contributed sessions covering the latest analytical techniques, their applications, and attempts to predict “what’s next”. So tie on your napkin, we’re going to sample the tech sessions from Pittcon 2002.

Biotech Breakthroughs
“Biology is an information science,” declared Leroy Hood in a special invited lecture. Hood led the team that invented the automatic gene sequencer in the 1980s. In 1999, he left his faculty position at the University of Washington to form the Institute for Systems Biology, an independent nonprofit organization based in Seattle. His goal is to describe biological systems and processes using the tools of mathematics.

Imaging and microscopy, two of the more practical techniques of biology-based science, have been around ever since Antony van Leeuwenhoek looked through his first lenses. Today’s digital microscopic images can be enhanced, manipulated, and analyzed. Increasing numbers of biologists map surface topographies using atomic force microscopy (AFM), once the provenance of silicon chip makers and physicists. Two-dimensional vibrational spectroscopic maps create chemical pictures of anything from painted surfaces to human bones to abnormalities in cells and tissues, providing important insights into materials defects and biological processes.

The instruments themselves are getting smaller as the lab-on-a-chip movement picks up momentum. Mass spectrometry, protein chips, and microarrays for detecting biomarkers are now used in cancer diagnostics. Small is good, but fast is better, according to several presentations on ultrafast separation techniques. One FTIR spectromicroscopy method uses synchrotron radiation to track real-time chemical changes in live cells.

Chemistry and biology come together in the study of the brain and its workings. The symposium “Return of the Mad Cow: Detection and Quantitation of Prions, Part II” continued last year’s discussion of how to diagnose, treat, and ultimately prevent the misfolded proteins and resulting holes in brain tissue that are the main symptom of prion diseases.

Brian Nunnally of Eli Lilly and Co. opened the session on a pessimistic note: “In this country, we are wise enough not to search for something that we don’t want to find”, referring to a lack of research and uncertainties as to the numbers of animals and people affected by prion diseases in the United States.

However, Ruth Gabizon, an Israeli researcher, offered some hope in the form of a test being readied for commercialization that can detect PrP^Sc, the prion protein, in a patient’s urine before clinical symptoms appear.

Other familiar chemistry techniques are crossing over to the biology lab as well. Diffusion NMR spectroscopy maps ligand–protein interactions, and software for predicting NMR spectra promises to facilitate characterizing pharmaceutical and natural product structures. Top-down FT-MS provides extensive characterization of large protein molecules, an application that will be increasingly useful in the development of proteomic science.

DNA mismatches can be detected using electrostatic surface plasmon resonance. New developments in elemental analysis center around portability (for field analysis), high throughput, and lower detection limits. For example, a new AA modification can be used for direct determination of heavy metals in human blood and plasma.

Sensor technology has also made great strides in recent years. Ionophore-based sensors can now detect simple ions such as magnesium and fluoride or more complex entities including dendrimers and impurities in polymeric membranes. Biosensors can now detect Salmonella, measure zinc ion release from cortical neurons, measure intracellular magnesium levels in viable cells, and track pH levels in biomedical and clinical applications.

Not all the interest was focused on instruments and lab methods, however. Regulatory compliance strategies were also a major presence in the technical talks and press conferences. One software vendor declared to members of the press that 21 CFR Part 11 was “the pharmaceutical industry’s Y2K problem”, recalling the flurry of software development that kept programmers working overtime in preparation for January 1, 2000. The current programming frenzy is in response to stepped-up enforcement of the U.S. Food and Drug Administration’s August 20, 1997, regulation covering electronic record-keeping and electronic signatures. The term “21 CFR Part 11-compliant” has become a required feature for software sold to the pharmaceutical and biotech industries.

Farming and Food
What does ion mobility spectrometry (IMS) have to do with the faded streak in the $70 cotton shirt you just bought? Lately, farmers in the U.S. haven’t gotten top dollar for their cotton because anything from polymer baling twine to windborne plastic grocery bags can find its way into cotton bales. During processing, vapors from this polymer detritus coat the cotton fibers, and the resulting fabric doesn’t hold dye uniformly. IMS is an up-and-coming method for sleuthing out the sources of stray plastic vapors, the first step in finding a way to eliminate the problem.

The links between biotechnology, agriculture, and food science have proliferated in recent years. With our increasingly global supply system for groceries, food safety is a major concern. Food safety standards vary from country to country, as does the thoroughness of customs inspections. Biosensors and bioanalytical microsystems have been pressed into service as the means of monitoring food safety. Integrated systems incorporating microelectromechanical systems (MEMS), nanotechnology, genetic platform arrays, and electrochemical microarrays provide a sophisticated means of molecular identification.

Nutrient assessment is taking on an increasingly important role as humanitarian organizations identify and develop food products that can be transported and stored easily while providing dietary essentials to people in developing and war-torn nations.

Genetically engineered or modified (GM) crops and foods that grow bigger and make their own pesticides are being touted as a boon to developing nations. Many people distrust these “frankenfoods”, however. The “Genetically Modified Foods: Feast or Frankenfoods?” symposium discussed the benefits, concerns, ecological effects associated with GM foods, as well as analytical methods for detecting genetic modifications.

In countries where basic survival is not at stake, food analysis focuses on factors such as fat content, pesticides, and carcinogens. Chromatographic techniques including thin-layer chromatography and ion-trap GC-MS-MS monitor pesticide levels in vegetables, and solid-phase microextraction GC-MS tracks levels of the suspected carcinogen ethyl carbamate (urethane) in beverages. Highly inert chromatography columns bring sulfur detection down to the ppb level, and automated thermal desorption GC-MS can measure lipid oxidation, an important factor in determining food freshness.

Many of the methods presented at the meeting were aimed at extracting beneficial agents or removing undesired compounds from food products. Specially designed adsorption filters remove sulfur compounds from beverage-grade CO₂ to prevent unwanted tastes and odors.

Pharmacologically significant compounds in nutraceutical plant extracts can be purified using a mass-directed autopurification method, and new food science techniques are being used to prevent heterocyclic amines (mutagenic compounds) from forming when beef is cooked.

Tracking Toxins
Your ecosystem may be safe from engineered genes, but what about combustion products, pesticides, and solvents? This year, Pittcon offered numerous presentations on environmental monitoring and analysis methods.

Air sampling and analysis methods continue to develop, and new technologies, such as cavity ringdown spectroscopy, are emerging. Membrane extraction systems assist in measuring biogenic emissions, and new methods are available to assess the mutagenicity of mineral and biogenic oils carried on smoke particles. Environmental aerosols are usually examined in the aggregate, but one research group is using an aerosol time-of-flight MS (TOF-MS) to study the size and composition of single airborne particles. The resulting particle counts can then be converted mathematically to chemical concentrations.

Another group has developed a series of surface acoustic wave sensors that can distinguish between isomers of various organic compounds in the vapor phase. These sensors, formed from self-assembled monolayers of liquid-crystalline polymers, form a “picket fence”, through which only planar molecules can pass.

One symposium devoted entirely to sulfur in transportation fuels addressed concerns arising from the tighter new regulatory standards for gasoline. Techniques used include pulsed flame photometry, chemiluminescence, and GC-atomic emission detector (AED). Sulfur compounds can be distinguished from one another using HPLC for sample prep and GC-MS for analysis. Various GC and “hyphenated” GC techniques are good for rapid analysis of refinery gas components and cross-contaminants in gasoline, diesel, and kerosene, but they can spot low levels of oxygenates and aromatics in fuels as well.

Cold-vapor AA techniques continue to push down the detection limit for mercury, an important factor in determining compliance with environmental regulations and remediation targets. Spectrometers with dual atomic fluorescence detectors have also been called into service for ultra-trace mercury analysis.

ICP-MS gets into the forensics game by detecting trace metals in human plasma. In one case study, IC-ICP-MS was used to quantify and identify the species of arsenic compounds in the blood, urine, and well water of a family that was suffering from arsenic poisoning.

Another research group compared pesticide and PCB levels in human serum specimens from the 1940s, 1970s, and the present.

Detecting the Dark Side
Last year, we were reminded that polluters weren’t the worst enemies we had. “Detection of Terrorist Weapons”, a Pittcon symposium topic for at least six years, suddenly loomed as large for the average citizen as for the FBI and CIA. This year’s session, organized by David Walt of Tufts University, was placed on the schedule in spring 2001, before we knew about anthrax-tainted letters and airplane passengers wearing shoes rigged with explosives.

Gas chromatography and TOF-MS have been pressed into service to detect explosives in wastewater. Mass spectrometry is now being used as a field detection method, and photoionization MS methods screen for chemical and biological weapons. Conventional HPLC and GC techniques can’t detect peroxide-based explosives, but reversed-phase HPLC followed by photochemical derivatization provides peroxide explosives with a tell-tale fluorescent tag that can be detected, even when the explosive is present in trace amounts.

Although terrorist activities have been grabbing headlines, the police spend much more time dealing with mundane crimes. A symposium on bloodstain analysis explored recent advances in methods to reconstruct events, collect and preserve evidence, and analyze dried and aging bloodstains using AFM and spectroscopic techniques.

Drugs also have a dark side. Collecting evidence and identifying drugs and their metabolites from an ever-growing list of designer drugs and amateur-produced products poses a formidable challenge. Gas chromatography, a laboratory mainstay, has been used to detect anything from tetrahydrocannabis levels in hair samples to the designer drug ketamine. Outfitting a GC instrument with IR and mass-selective detectors helps to verify the drug Ecstasy and its isomeric forms, and a library of near-IR “mug shots” lets investigators spot counterfeit Prozac. Solid-phase extraction ion mobility spectrometry is a useful tool for detecting illegal narcotics and their metabolites in urine.

Mathematics, more specifically, chemometrics, becomes an analysis technique when multivariate curve resolution is used to detect heroin in drugs of abuse. Field-portable instruments (FTIR units are one example) bring the laboratory to the crime scene, providing rapid analysis and minimizing sample degradation during transport.

The Newest in Nano
Nanotechnology is the other big development of the decade. In nanomaterials, the empty spaces play just as important a role as the structures themselves. For example, aerogels (typically made of silica or other oxides) have delicate frameworks that resemble clusters of tiny beads enclosing interconnected pockets of empty space. These pockets can be filled with just about anything you can imagine, from organosilanes that fluoresce at the flip of a switch, to platinum fuel cell catalysts, to ruthenium oxide nanowires that supply electricity to the guest-molecule tenants of the “nano-apartments” in the aerogel.

Quantum dots, once a laboratory curi osity, are finding application as color-coded biomarkers. These tiny semiconductor crystals emit visible, UV, or IR light in characteristic colors, depending on their chemical composition and particle size.

Quantum dot clusters with specific color combinations are encapsulated in polymer beads. The beads are attached to organic functional groups that attach preferentially to various types of cells, such as cancer cells. When the cells are illuminated with the right wavelength of light, the outlines of the tagged cell structures glow like strings of holiday lights. This technique has been tested on living mice, and the next challenge for researchers will be to adapt it for use as a diagnostic tool in humans.

Other nanomaterials form tiny tips for AFM and scanning tunneling microscope probes, mapping the surfaces of anything from alloys to amoebas. Some chemically selective tips can be used to create chemical maps of surfaces. Luminescent zinc nanosensors and ion-selective micrometer-sized fiber-optic sensors called optodes are two ways of producing chemical images of subcellular-level processes in real time.

Spec and Chips
Several new spectroscopic techniques are probing nanomaterials at the single-particle and single-molecule levels. For example, inductively coupled plasma-optical emission spectroscopy (ICP-OES) can determine trace elements in precious metals, an important tool for the semiconductor industry, which places rigorous demands on the purity of metals used for circuitry.

Glow discharge OES is now used to optimize quantitative, nanometer-scale depth profile analyses of organic coatings. Electrophoretic “sample stacking” concentrates analytes by 2–3 orders of magnitude, making it possible to analyze trace impurities using NMR.

Molecular computers are closer to becoming a reality as studies in long-range electron transfer continue to provide new insights. Tunneling-based nanoelectronics and organic heterojunctions shared the stage with junctions based on conjugated carbon–carbon bonding. Nanosized bar code identification tags are just the thing for protein and metabolite profiling.

The push for rapid genomic and proteomic analysis has spurred new developments in microfluidics and lab-on-a-chip devices. Plastic substrates are being designed with an eye toward biocompatibility and electroosmotic properties, and molecular imprinting assists with separations applications.

Biomimetics makes an appearance in “soft” nanofluidic devices that use lipid nanotube–vesicle networks. Recent advances in microfluidics make it possible to perform continuous-flow polymerase chain reactions—and assay nitrated explosives— on microchips. One device performs a simultaneous determination of hormone release and intracellular calcium ion concentration, an important development for tracking cellular processes.

Revising the Recipe
A lot has changed between 1950 and 2002, but those first Pittcon attendees would recognize many of the ingredients in this year’s gumbo: spectroscopic, photometric, and electrochemical methods. Those folks would find a lot to be amazed at, too. Steel mills have largely given way to semiconductor plants, labs are on chips as well as benchtops, and smelters have given way to fermentation vats.

Much of the cutting-edge research from this year’s technical sessions may appear in the vendor’s exhibits at Pittcon 2052. Allen Bard noted in his plenary lecture that Dick Tracy’s wrist radio, which was pure fancy in 1946, looks suspiciously like today’s cell phone. The Pittcon gumbo recipe changes from year to year, new ingredients are added, and the bowl keeps getting bigger.