Electrochemical Behavior and Determination of Uric Acid at Reduced Graphene Oxide Modified Electrode

KeyWord:graphene  modified electrode  uric acid  electrochemical behavior

Abstract:

      Electrochemical behavior and response of uric acid£¨UA£© was investigated at the chemically reduced graphene oxide£¨RGO£©modified glassy carbon£¨GC£© electrode£¨RGO/GC£© by cyclic voltammetry,chronocoulometry and AC impedance method.The results showed that£¬in pH 6ª±0 PBS buffer solution,the electrochemical oxidation of UA at the RGO/GC modified electrode was irreversible and controlled by diffusion.Some kinetic parameters such as the number£¨n£© of the electron transferred,the effective area£¨A£© of the modified electrode and the diffusion coefficient£¨D£© were calculated to be 2,0.182 cm2 and 1.51¡Á10-6 cm2?s-1,respectively.A good linear relationship between peak current and concentration of UA was observed in the range of 5.0¡Á10-6-1.5¡Á10-4 mol/L,which met the equation of Ip£¨¦ÌA£© =6.457+367.5c£¨mmol/L£©£¨r=0.995 7£©.The RGO/GCE modified electrode was successfully applied in the determination of UA with a detection limit of 2.7¡Á10-7 mol/L and recoveries of 98%-100% .