Differential Electroanalytic Oxidation of Dopamine and Ascorbic Acid at Nickel Oxide Nanoparticles Modified Glassy Carbon Electrode

A simultaneous determination of Dopamine (DA) and ascorbic acid (AA) in their coexistence at nickel oxide nanoparticles modified glassy carbon electrode (nano-NiO x /GCO x ) have been achieved. (Nano-NiO x /GCO x ) have been prepared by electrodeposition of nickel nanoparticles, and the thus prepared nickel nanoparticles have been subjected to electrochemical oxidation in alkaline medium for the formation of nickel oxide. Modified electrodes have been electrochemically and morphologically characterized. Effect of loading level of nickel was investigated by changing the number of potential cycles for the deposition of nickel nanoparticles, i.e., 1, 2, 5 and 10 potential cycles were used. Also, the experimental and instrumental parameters are optimized. The results have shown that modified electrode displayed excellent electroanalytic activity towards the oxidation of dopamine (DA) and ascorbic acid (AA) enabling the electrochemical determination of DA and AA using square wave voltammetry in their coexistence. Key Words: Nanomaterials, Electroanalysis, Electrocatalysis, Nickel Oxide, Glassy Carbon Electrode, Dopamine, Ascorbic Acid