Study of Chitosan-TiO2 Nanoparticles Composite Film Modified Electrode for the Electrochemical Oxidation Behaviour of Nitrite

Abstract

An electrochemical sensor for sensitive and convenient determination of nitrite, which was based on the nano-TiO₂/chitosan composite film modified electrode, was developed. Owing to the unique properties of nano-TiO₂ such as huge surface area, strong adsorptive ability and subtle electronic properties, the electrochemical oxidation signal of nitrite significantly increases at the nano-TiO₂/chitosan based electrochemical sensor, suggesting that the nano-TiO₂ exhibits obvious enhancement effect to the determination of nitrite. Based on this, a sensitive and convenient electrochemical method was developed for the determination of nitrite. The oxidation current was linearly related to nitrite concentration over the range of 5.0 × 10^-6-1.0 × 10^-3 M, with a detection limit of 1.28 × 10^-6 M. The results indicate that the nano-TiO₂/chitosan composite film modified electrode is an attractive thin film for the development of fast, simple and sensitive sensors.