Differential pulse voltammetric investigations of uric acid in aqueous and micelle systems

283-289Differential pulse voltammetric behaviour of uric acid has been studied in phosphate buffers of pH 2.3-11.2 at glassy carbon electrode. A well-defined 2e, 2H+,pH-dependent oxidation peak has been noticed and the conjugate base found as the electroactive species. Cationic surfactants have been found to significantly effect the Ep and ip. At concentrations below CMC, the change in Ep is predominantly due to adsorption effects, whereas at concentrations above CMC electrocatalysis and micellar catalysis shifted the Ep towards less positive potentials. The voltammetric behaviour in the presence of surfactants indicates that the 2e oxidation proceeds in two 1e steps and the formation of cationic free radical is suggested. The products of electrode reaction have been found to be the same in aqueous and micelle systems