Electrochemical Characterization of Gold 6-Amino-2-mercaptobenzothiazole Self-Assembled Monolayer for Dopamine Detection in Pharmaceutical Samples

A new sensor, gold-6-amino-2-mercaptobenzothiazole (6A2MBT), was fabricated via a self-assembly procedure. Electrochemical properties of the monolayer were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The modified electrode showed excellent antifouling property against the oxidation products of DA, allowed us to construct a dynamic calibration curve with two linear parts, 1.00 x 10(-6) to 3.72 x 10(-4) and 3.72 x 10(-4) to 6.42 x 10(-4) M DA, with correlation coefficients of 0.997 and 0.992 and a detection limit of 1.57 x 10(-7) M DA by using differential pulse voltammetry (DPV), respectively. Finally, the performance of the Au-6A2MBT modified electrode was successfully tested for electrochemical detection of DA in a pharmaceutical sample.