Electrochemical Determination of Nitrite Based on Gd Doped Nano Titanium Dioxide-Modified Gold Electrode

Abstract

A simple and reliable method for electrochemical determination of nitrite based on Gd doped nano titanium dioxide (Gd-nano-TiO2) modified gold electrode was well developed in this paper. Using cyclic voltammetry, the modified electrode shows electrocatalytic activity for oxidation of nitrite in 0.10 mol×L-1 sulfuric acid solution (pH=0.70). The catalytic peak current was found to be linear with nitrite concentration in the range of 2.0´10-6 ~ 2.0´10-4 mol×L-1, with a detection limit of 1.1´10-6 mol×L-1 (S/N=3). Compared with spectrophotometry, the Gd-nano-TiO2 modified Au electrode could be used for the determination of nitrate in the ham sausage samples with a satisfactory recovery of 95.9 ~ 103.2%, showing its promising application in safety evaluation for food.