▎ 摘　　要

Nitrogen-doped graphene was synthesized by one. step hydrothermal method. A nitrogen-doped graphene-chitosan modified electrode (N-GN-CS/GCE) was prepared and the electrochemical behavior of uric acid in the presence of a large amount of ascorbic acid was investigated at the modified electrode. The peak current of uric acid at the modified electrode was 7 times as that at unmodified electrode. The peak separation of uric acid and ascorbic acid was 362 mV and uric acid could be accurately determined in the presence of a large amount of ascorbic acid. Some experimental parameters such as dopping volume, pH and scan rate were optimized and a standard curve was also established using differential pulse voltammetry. The linear range between the peak current and the concentration of uric acid was 0.1 similar to 20 mu mol/L and 20-400 mu mol/L, and the detection limit was estimated to be 0.01 mu mol/L. The proposed method was applied to the analysis of uric acid in human urine sample with recoveries between 99.7% and 103.4%.