[Differential pulse-voltametric determination of dopamine using pretreated electrochemical electrodes]

The electroanalytical method proposed permits a sensitive and selective determination of dopamine in the presence of ascorbic acid applying a fast galvanostatic pretreatment of the carbon electrodes. The effect of the electrochemical pretreatment at glassy carbon electrode (A = 0.8 mm2) was compared with that of carbon fibre array electrode (A = 0.15 mm2). Both types of electrodes showed approximately the same detection limit for dopamine of about 1.10(-7) mol/l dopamine. In comparison to the polished electrodes the sensitivity is improved by a factor of 100. The galvanostatic pretreatment led also to a drastic improvement of selectivity by cathodic shift of the ascorbic acid peak potential.