Electrochemical determination of dopamine using zinc-oxide rod modified carbon paste electrode

Abstract

An excellent limit of detection 2.7 ?M for Dopamine was achieved voltommetrically using ZnO rod modified carbon paste electrode. Zinc oxide rods (ZnOR) were synthesized using low temperature hydrothermal method. The structural and morphology study of ZnOR structures was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques and energy dispersive X-ray (EDX) spectroscopy. As-synthesized ZnOR were used to construct the modified carbon paste electrode (ZnOR/CPE) and investigated for the dopamine (DA) detection. The modified electrode showed excellent catalytic activity towards the DA at pH 7.0 phosphate buffer solution. The cyclic voltammetry (CV) and differential pulse voltammetry techniques (DPV) were used for DA determination. Under optimum conditions, the fabricated sensor exhibits best sensing performance with high sensitivity of 1080 ?A mM?1cm?2with linear response range obtained from 0 800 ?M of DA for DPV. The ZnOR/CPE exhibits excellent sensitivity, greater stability and reproducibility. 2016 American Scientific Publishers. All rights reserved.