▎ 摘　　要

A highly sensitive electrochemical sensor for the simultaneous determination of SO32- and NO2- based on a glassy carbon electrode (GCE) modified with grapheme (GR)-chitosan (CS) and gold nanoparticles (AuNPs) has been developed. The GR and GR-CS/AuNPs GCEs were characterised using a transmission electron microscope (TEM). The electrochemical behaviours of SO32- and NO2- at the GR-CS/AuNPs GCE were investigated using cyclic voltammetry (CV). The chemically modified electrode displayed excellent electrochemical catalytic activities towards sulphite and nitrite. Linear relationships between the values of the oxidation peak current and the concentration of SO32- and NO2- were obtained in the ranges of 5-410 mu mol/L (R=0.9986) and 1 - 380 mu mol/L (R = 0. 9940) with detection limits (S/N = 3) of 1 mu mol/L and 0.25 mu mol/L, respectively. This GR-CS/AuNPs GCE showed many advantages in terms of stability, sensitivity, facility and economy. The proposed method was employed to analyze real samples with recoveries of 97.2% to 102.6%.