Activity of SiDbCl in the Electrooxidation of Ascorbic Acid, Dopamine, and Uric Acid

Selective electroanalytical responses for ascorbic acid, dopamine and uric acid at a carbon modified electrode based on 3-n-propyl-1-azonia-4-azabicyclo[2.2.2]octane silsesquioxane chloride (SiDbCl) is reported. The overlapped peaks observed at an unmodified electrode are resolved into three well defined voltammetric peaks allowing the simultaneous determination of the three species. Detection limits of 37, 0.3 and 0.1 mu moL(-1) of ascorbic acid, dopamine and uric acid, respectively, were calculated from calibration curves based on differential pulse voltammetric experiments performed in Britton-Robinson buffer solution at pH 7.04.