Aminothiophenol Furfural Self-assembled Gold Electrode Sensor for Determination of Dopamine in Pharmaceutical Formulations

A new Schiff base 2-aminothiophenol furfural self assembled monolayer (SAM) has been fabricated on a bare gold electrode as a novel sensor for determination of dopamine. Electrochemical impedance spectroscopy was utilized to investigate the properties of the Au 2-aminothiophenol furfural self assembled monolayer modified electrode (Au ATF SAM-ME) using the [Fe(CN)6]3-/4- redox couple. The electrochemical behavior of dopamine on the Au ATF SAM-ME was studied by cyclic voltammetry and differential pulse voltammetry, using phosphate buffer solution as supporting electrolyte. The ascorbic acid has no response on the modified self-assembly electrode. A calibration curve was obtained for dopamine in a linear range of 2.0 × 10-6 to 1.0 × 10-4 M. The detection limit for dopamine was found to be 3.0 × 10-7 M. The results indicated that the Au ATF SAM-ME could be employed for the determination of dopamine in pharmaceutical formulations.