Journal of Electroanalytical Chemistry, Vol.834, 71-78, 2019
Fabrication of poly (sudan III) modified carbon paste electrode sensor for dopamine: A voltammetric study
Owing to the challenges faced in simultaneous determination of dopamine(DA), uric acid(UA) and ascorbic acid (AA) in mixtures by electrochemical method, the present work is aimed at developing a simple, sensitive and selective sensor using sudan III as the modifier. The poly (sudan III) modified carbon paste electrode (PS/MCPE) was prepared by electropolymerization of sudan III monomer on the surface of bare carbon paste electrode (BCPE). Electrochemical sensing properties of poly (sudan III) MCPE were evaluated by cyclic voltammetry for individual analytes and findings revealed that it has a good electrocatalytic activity towards the determination of dopamine (DA), uric acid (UA) and ascorbic acid (AA) characterized by a low detection limit of 9.3 x 10(-6) M, 1 x 10(-5) M and 4.5 x 10(-5) M for DA, UA and AA, respectively. The scan rate study reveals that the electrode process is adsorption-controlled. The simultaneous determination of the analytes in a mixture showed that the modified electrode exhibits an outstanding selectivity towards DA, UA and AA with their distinct oxidation potentials occurring at 0.14 V, 0.27 V, and -0.07 V, respectively. The fabricated modified electrode sensor exhibited excellent electrocatalytic properties towards the determination of DA, UA and AA with satisfactory results.
Keywords:Sudan (III);Electropolymerization;Dopamine;Uric acid;Ascorbic acid;Simultaneous determination;Carbon paste electrode