Eletropolymerization of Niacinamide for Fabrication of Electrochemical Sensor: Simultaneous Determination of Dopamine, Uric Acid and Ascorbic Acid

Two polymeric thin film modified electrodes, poly-niacinamide/glassy carbon electrode (poly-NA/GCE) and poly-nicotinic acid/glassy carbon electrode (poly-NC/GCE), have be fabricated at glassy carbon electrodes by simple electropolymerization of niacinamide (NA) in different potential scan ranges of cyclic voltammetry (CV). These two electrodes all showed catalytic ability towards the oxidation of dopamine (DA), uric acid (UA) and ascorbic acid (AA) by obvious reductions of overpotentials, giving well-resolved voltammetric peaks, which allow simultaneously determination of DA, UA and AA. The poly-NC/GCE showed even higher electrocatalytic activity than the poly-NA/GCE. The electrochemical behavior of poly-NC/GCE was investigated by CV and differential pulse voltammetry (DPV) for determination of DA, UA and AA. The linear ranges of the concentration for the determination of AA, DA and UA using DPV were 75-3000, 0.37-16 and 0.741-230 mu mol.L-1, respectively. The slopes of the linear calibration curves for the detection were estimated to be 5.6, 1140 and 102 mA.L.mol(-1) for AA, DA and UA, respectively. The poly-NC/GCE shows excellent sensitivity, good selectivity and antifouling properties.