▎ 摘　　要

Poly (dienedimethylammonium chloride) (PDDA) functionalized silver nanoparticles (AgNPs) prepared with PDDA as the protective and reductive agents was combined with graphene oxide (GO) to prepare PDDA functionalized cubic silver nanoparticles (C-AgNPs)/GO composite, which was then modified on a glassy carbon electrode (GCE) to form C-AgNPs. PDDA/GO/GCE. The surface morphologies of different modified electrodes were characterized by scanning electron microscope (SEM), and their corresponding cyclic voltammetric (CV) behaviors were investigated, indicating that the composite of C-AgNPs-PDDA/GO exhibited excellent electrocatalytic oxidation activity to DA and NO2-. By using differential pulse voltammetry, the responses of C-AgNPs-PDDA/GO/GCE were linear in the ranges of 0.030-0.300 mu mol/L and 0.300-300 mu mol/L with detection limit of 9.8 nmol/L (S/N = 3) for DA, and 30.0-2300 mu mol/L with detection limit of 12.6 mu mol/L (S/N = 3) for NO2-, respectively. The modified electrode displayed good selectivity, reproducibility and stability, and could be used for the simultaneous determination of DA and NO2- in human serum samples with recoveries of 97.4%-104.2% and 98.0%-102.8%, respectively. Compared with spectrophotometric method, the determination results were satisfactory, showing that the modified electrode possessed a potential application value.