Polyoxometalate/carbon black modified glassy carbon electrode for the detection of dopamine

Dopamine (DA) is a crucial neurotransmitter in the central nervous system (CNS) of human and multicellular animal brains. In this paper, we report for the first time the synthesis of C/PWA composites by doping phosphotungstic acid (PWA) on carbon black nanoparticles by impregnation method. The synthesized materials were characterized and corroborated using high-resolution scanning electron microscopy, X-ray diffraction spectroscopy (XRD) and Fourier transform infrared spectroscopy. The synthesized C/PWA composite modified glassy carbon (GC) electrodes were used as selective electrocatalysts for dopamine (DA) oxidation process. The electrochemical redox behavior of DA was studied with cyclic voltammetry (CV). Under optimized conditions, DA was detected by differential pulse voltammetry (DPV) and the calibration plot showed linearity ( R 2  = 0.9988) over the range of DA concentrations of 10 µM-600 µM with a detection line of 0.1 µM. The sensor's capability to detect DA in commercial DA injections in real time has been successfully demonstrated.