Dopamine Detection on Boron-doped Diamond Electrodes Using Fast Cyclic Voltammetry

A new method is proposed for the accurate and reproducible detection of dopamine using cyclic voltammetry on boron-doped diamond (BDD) electrode. It is shown that reproducible voltammograms can be obtained when applying a relatively high scan rate (100 V s(-1)) during the detection measurements. For lower scan rates (1 V s(-1)), it is proven that electrode fouling occurs due do the deposition of a polymer at the electrode surface arising from the oxidation of aminochrome. Cyclic voltammetry measurements of the [Fe(CN)(6)](3-)/[Fe(CN)(6)](4-) couple performed before and after dopamine detection on BDD and glassy carbon electrodes have shown that the electrochemical activity of the electrode decreases only at low scan rates for BDD dopamine (DA) detection, which leads to electrode poisoning whereas the activity remains unchanged for higher scan rates. However, on glassy carbon electrodes, the electrochemical activity of the material decreases after DA detection measurements independently of the scan rate applied. Therefore, this study shows that electrode fouling during the detection of dopamine by cyclic voltammetry can be avoided only when using BDD electrode but also only for high applied scan rates.