A novel electrochemical method for the detection of nerve gases

A novel electrochemical detection technique was developed for selective det ection of nerve gases based on double-potential-step chronoamperometry (DPS CA) and the oxidation of nerve gas by electrochemically generated iodine. D iethyl cyanophosphonate (DECP) was used as a nerve gas mimic. The double-po tential-step chronoamperometry has a detection limit of 2 x 10(-6) M for DE CP and is more sensitive than the currently available electrochemical techn iques for detection of nerve gases. The DPSCA technique, which uses the rat io of anodic to cathodic currents as a measuring parameter, was found to be more sensitive than the single-potential-step technique. Changes in the ar ea and activity of the electrode and the concentration of the catalyst do n ot influence the current ratio, which contributes to the high reproducibili ty of the DPSCA technique. (C) 1999 Elsevier Science S.A. All rights reserv ed.