Simultaneous Detection of Dopamine and Acetaminophen by Modified Gold Electrode with Polypyrrole/Aszophloxine Film

The differential pulse voltammetric method was developed for simultaneous determination of dopamine (DA) and acetaminophen (AC) using the Ppyox/AZ/Au (poly overoxidized pyrrole–aszophloxine–gold) modified electrode. Polypyrrole film was prepared by incorporation of aszophloxine (AZ) as doping anion, during the electropolymerization of pyrrole onto a gold (Au) electrode in aqueous solution using the cyclic voltammetric (CV) technique. Then the polypyrrole film was overoxidized at constant potential. Well-separated voltammetric peaks were observed for dopamine (DA) and acetaminophen (AC) with peaks separation of about 200 mV. The current of the oxidation peaks showed a linear dependent on the concentrations of DA and AC in the range of 0.1–30 μM and 0.2–100 μM respectively. The detection limit of 0.05 and 0.08 μM (S/N = 3) were obtained for DA and AC respectively. The modified electrode was used for determination of DA and AC in some real samples such as human serum and tablet samples.