Electrochemical Characterization of Glassy Carbon Electrode and Boron-doped Eledctrode for Determination of Quercetin

The present paper reports electrochemical, as cyclic voltammetry and amperometry, was studies of the process of electrooxidation of quercetin at a glassy carbon electrode and boron-doped diamond electrode, in 0.05 M phosphate buffer in 20% ethanol solution. Quercetin electrochemical oxidation was an irreversible reaction at the glassy carbon electrode. The oxidation mechanism proceeds in sequential steps, related with the catechol and resorcinol groups and the oxidation is pH dependent. The quercetin quantitative analysis at glassy carbon electrode was detected by amperometry in phosphate buffer (pH 6.0) with potential 0.6 V. The results were received high sensitivity, excellent dynamic range as 0.0005-0.412 mM and 0.36-1.60 mM, and a low detection limit at and 0.2 m M (S/N = 3), respectively.