▎ 摘　　要

An electrochemically reduced graphene oxide/gold nanoparticle-chitosan (ERGO/AuNP-CS) composite film modified glassy carbon electrode (GCE) was constructed by directly electrochemical reduction of GO, and then assembly of AuNP-CS polycation on the surface. The surface morphologies of different modified electrodes including bare GCE, GCE/GO, GCE/ERGO and GCE/ERGO/AuNP-CS were characterized by scanning electron microscopy (SEM). The differential pulse voltammetric behaviors of the electrodes were investigated, and the results indicated that the composite of ERGO/AuNP-CS exhibited excellent electrocatalytic oxidation activity to uric acid (UA) molecule. In 0.10 mol/L of phosphate buffer solution (pH=6.5) with a scanning rate of 100 mV/s, the proposed composite film modified electrode showed a linear electrochemical response to UA in the range of 0.05-110 mu mol/L with a detection limit of 12.4 nmol/L (S/N=3). The electrode displayed good selectivity, reproducibility and stability in the determination of UA in human serum and urine samples with a recovery of 93.8%-104.1%. The detection results were agreed with those of conventional spectrophotometry and uricase Kit methods.