Selective Electrochemical Detection of Dopamine in the Presence of Ascorbic Acid at Anodized Diamond Thin Film Electrodes

Abstract

Selective, highly stable determination of dopamine (DA) was achieved in cyclic voltammetric and chronoamperometric measurements carried out at electrochemically treated conductive diamond film electrodes. The treated electrodes exhibited substantial shifts in the positive direction for the peak potential for ascorbic acid (AA) oxidation, thus making it possible to discriminate between the DA and AA responses. Linear calibration curves were obtained for both a higher concentration range and a lower range using voltammetry and chronoamperometry, respectively. The detection limit appears to be on the order of , which is among the lowest values reported thus far. Selectivity was also achieved in aqueous solution using more stringent electrochemical treatment, but the effect was relatively short‐lived (up to 2 h). ©1999 The Electrochemical Society