A “humid electronic nose” for the detection of nerve agent mimics; a case of selective sensing of DCNP (a Tabun mimic)

Abstract

A humid electronic nose device based on pulse voltammetry has been applied to detect nerve agentsimulants in gas phase. The humid electronic nose consists in a polypropylene piece which containsan array of eight metallic electrodes (i.e., Ir, Rh, Pt, Au Ag, Co, Cu and Ni) divided into two sets of fourworking electrodes housed inside a homemade steel cylinder, and a salt bridge connection to a referenceelectrode. The electrochemical system is fitted to a nylon membrane damped with a background solutionof sodium tetraborate 0.01 M by a second polypropylene piece. The PCA analysis demonstrated that thesystem is able to discern principal organophosphorous nerve agent mimics (DCP, DCNP and DFP) fromorganophosphorous derivatives and some other potential interferents. Besides, the PLS quantificationanalysis showed sound accuracy in the concentration prediction for DCNP in air, good linearity and alimit of detection (LOD) of some a few ppm.