Electrochemical determination of Uric acid by persian blue modified electrode with sol gel method

An Au electrode modified with Persian blue (PB), has been applied to the electrocatalytic oxidation of uric acid, which reduced the overpotential by about 165 mV with obviously increased current response. The cyclic voltammetry method was employed to characterize the electrochemical behavior of the chemically modified electrode. The electrocatalytic efficiency of the modified electrode towards uric acid oxidation process depends on the solution pH value, and the optimum pH value for the oxidation of uric acid is 7.0. The overall number of electrons involved in the catalytic oxidation of uric acid and the number of electrons involved in the rate-determining steps are 2, respectively. And diffusion coefficient of the uric acid compound was estimated using the chronoamperometry technique. The proposed method is simple and rapid with excellent selectivity and sensitivity within the linear range of 0.2-2 mM uric acid with a detection limit of M and correlation coefficient R2 = 0.9913.