Simultaneous electrochemical determination of ascorbic acid and uric acid using poly(glyoxal-bis(2-hydroxyanil)) modified glassy carbon electrode

In this paper, a novel polymer film of poly(glyoxal-bis(2-hydroxyanil)) P(GBHA), was prepared by electropolymerization of glyoxal-bis(2-hydroxyanil) (GBHA) on a glassy carbon electrode (GCE), and this electrode was utilized for the simultaneous detection of the ascorbic acid (AA) and uric acid (UA). The influences of electrochemical synthesis parameters on the electron transfer properties of P(GBHA) films were investigated, and the optimum synthesis conditions providing the lowest electron transfer resistance were determined. Scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) methods were employed for the characterization of the P(GBHA) film prepared under the optimum conditions. The electrochemical sensor exhibited high electrocatalytic activity toward the oxidation of AA and UA. The linear response ranges for the individual determination of AA and UA were 1.0-2000 and 1.0-200 mu mol L-1 with the detection limit of 0.26 and 0.3 mu mol L-1, respectively. These results present that the P(GBHA) is a promising substance for the production of electrochemical sensors with high sensitivity. (C) 2015 Elsevier B.V. All rights reserved.