Electrochemical codeposition of gold particle–poly(2-(2-pyridyl) benzimidazole) hybrid film on glassy carbon electrode for the electrocatalytic oxidation of nitric oxide

Abstract

A nitric oxide (NO) sensor was developed by coating gold particles (AuPs) dispersed poly(2-(2-pyridyl) benzimidazole) (PPBZ) film on glassy carbon (GC) electrode by cyclic voltammetry. The PPBZ film modification enhances the electron transfer kinetics and the AuPs increase the surface area and electrocatalytic activities of GC electrode. A 4.04 fold increase in anodic current with 100mV shifting of the peak potential towards less positive side was observed for the composite film modified electrode compared to that of bare GC electrode. The electron transfer coefficient, electron transfer rate constant, diffusion coefficient and catalytic rate constant for the electrooxidation of NO were investigated. The amperometric measurements revealed a linear range of detection from 1.7×10−8 to 2.0×10−6M with a detection limit of 3.7nM (S/N=3) and sensitivity of 6.45AM−1cm−2. The modified electrode possessed remarkable stability and reproducibility towards NO detection and was successfully applied for the detection of NO released from the living tissues.