2,3-Dimercaptosuccinic acid self-assembled gold electrode for the simultaneous determination of epinephrine and dopamine

Simultaneous determination of epinephrine (EP) and dopamine (DA) at 2,3-dimercaptosuccinic acid (DMSA) modified electrode was studied. The oxidation peaks of the mixture of EP and DA appeared at the same potential, but the cathodic peak currents were only linear to the concentration of DA, whereas the anodic peak currents were equal to the sum of individual anodic peak currents of EP and DA. Therefore, a novel electrochemical method for the simultaneous determination of EP and DA at a DMSA modified electrode (DMSA/Au electrode) by cyclic voltammetry was established. The DMSA self-assembled electrode showed good sensitivity, selectivity and stability and could be used to determine DA and EP, simultaneously, in the real application with satisfactory results.