J. Am. Chem. Soc., 129 (51), 15754 -15755, 2007. 10.1021/ja076821m S0002-7863(07)06821-7
Web Release Date: December 6, 2007

Copyright © 2007 American Chemical Society

Unbiased Selectivity Coefficients Obtained for the Pulsed Chronopotentiometric Polymeric Membrane Ion Sensors

Hasini Perera and Alexey Shvarev*

Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331-4003

alexey.shvarev@oregonstate.edu

Received September 11, 2007

Abstract:

We report here on the successful observation of the unbiased thermodynamic selectivity of ion-selective sensors working in normal pulse chronopotentiometric mode (pulstrodes). In contrast to ion-selective electrodes, the pulstrodes do not require careful counterbalancing of the transmembrane ionic fluxes to achieve unbiased thermodynamic selectivity. The pulstrodes can work under asymmetric conditions, which are often encountered in practice. The composition of the inner filling solution did not affect the sensor response, indicating that the transmembrane flux of primary ions was indeed effectively suppressed in the absence of ion exchanger. For the K-selective sensor considered here, an improvement of Mg discrimination by a factor of 1000 was demonstrated.


Download the full text: PDF | HTML