Development of ZnO Adorned Glassy Carbon Electrode for Voltammetric Sensing and Electro-Kinetic Investigations of Antihypertensive Drug Efonidipine

Abstract

The fast, accurate, and affordable determination of efonidipine (EFO) is the need of the time for human mental health. In this work, we proposed a ZnO-adorned glassy carbon electrode (ZnO/GCE) for the voltammetric sensing and electro-kinetic investigations of efonidipine in pharmaceutical samples. ZnO-decorated glassy carbon electrode exhibit enhanced electro-catalytic activity, higher surface area, rapid electron transfer rate, and enhanced electrical conductivity, these properties result in an amplified peak current response for the electro-reduction of EFO. The ZnO nanoparticles are synthesized by a simple and economical sol-gel method and characterized by XRD, SEM, and EDS techniques. The electro-kinetic studies of efonidipine on the ZnO fabricated glassy carbon electrode was investigated using CV, EIS, LSV, DPSV, and Chronocoulometry techniques. The diffusion-controlled electro-reduction of EFO produced three well-defined peaks in the cyclic voltammograms. The various electro-kinetics parameters like diffusion coefficient (Do), heterogeneous rate constant (Kh), electron transfer coefficient (α), and surface coverage (Γ) were evaluated and the mechanism of electro-reduction was proposed. The peak current in LSV and DPSV techniques shows a linear relationship with the concentration of EFO in the range of 0.14–0.98 µmolL− 1 with detection limits of 0.21 and 0.07 µmolL− 1, respectively. The proposed ZnO/GCE sensor demonstrates a cost-effective and environmentally compatible approach for the detection of efonidipine in pharmaceutical samples.