A simple and novel strategy for the simultaneous determination of dopamine, acetamidophenol and tryptophan based on poly(new coccine) film modified carbon paste electrode

A polymerized film of new coccine was deposited on a carbon paste electrode (CPE) by an electropolymerization technique. Electrochemical characterization of the modified electrode was investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The poly(new coccine) modified CPE exhibited excellent electrocatalytic activity towards the oxidation of dopamine (DA), acetaminophenol (AP) and tryptophan (Trp) simultaneously. Well defined and separated oxidation peaks were observed by CV. Linear calibration plots for the oxidation of DA, AP and Trp were obtained in the range of 0.7-200 mu M for DA, 1.5-120 mu M for AP, and 0.6-50 mu M for Trp. Detection limits of DA, AP and Trp were found to be 0.2, 0.3 and 0.2 mu M, respectively. With good selectivity and sensitivity, the present method has been successfully applied to the determination of DA, AP and Trp in pharmaceutical samples.