Nitric oxide sensor based on poly ( p-phenylenevinylene) derivative modified electrode and its application in rat heart

Abstract

A novel nitric oxide (NO) electrochemical sensor was fabricated by electropolymerization with two-pulse potential method in aqueous solution containing poly ( p-phenylenevinylene) derivative. The experimental results showed this sensor exhibits apparent current response to NO by cyclic voltammetry. Two anodic peaks potential are significantly shifted negatively compared with bare glass carbon electrode (GCE). Chronocoulometry were used to further validate the electron transfer process of NO oxidization on this sensor. The results indicated that oxidation of NO proceeds in two steps. The first step leading to NO 2 − involves one-electron transfer process and the second step corresponding to the oxidation of NO 2 − to NO 3 − involves two-electron transfer process. The amperometric response is linear with NO concentration ranging from 1.8 × 10 − 7 to 1.0 × 10 − 4 mol L − 1 with a linear coefficient of 0.9993. The detection limit of NO is 2.3 × 10 − 8 mol L − 1 (S/N = 3). After possible interferences were tested, NO release from the rat heart cells stimulated by L-arginine was measured using this sensor. The result is satisfactory.