Selective voltammetric detection of dopamine using ferrocene modified carbon paste electrode

Abstract

A selective sensor based on carbon paste electrode with ferrocene (Fc/CPE) has been investigated. The Fc/CPE was prepared for selective dopamine (DA) in presence of interference compounds as ascorbic acid (AA) and uric acid (UA). The Fc/CPE can well resolve the peak oxidation of DA, AA and UA. The modified electrode exhibited better electrocatalytic activity and catalytic efficiency 3.5 times higher than using the unmodified electrode. The electrochemical behaviours of DA at the surface of the modified electrode were studied by cyclic voltammetry (CV). Using differential sweep voltammetry (DPV) at the optimum condition the determination of DA was measured in the concentration range of 0.5 μM - 10 μM with a detection limit of 0.2437 μM and a correlation coefficient of 0.9995. The Fc/CPE has been applied to determination of DA spike into simulated sample and showed good recovery.