ZnO/rGO nanocomposite/carbon paste electrode for determination of terazosin in human serum samples

Abstract

Terazosin (TR) is used for the treatment of symptoms of an enlarged prostate. It also acts to lower blood pressure. Therefore, the determination of TR for dosage control of the drug in the body is very important. In this study, a carbon paste electrode (CPE) modified with ZnO nanoparticles and reduced graphene oxide (rGO) was used as a fast and sensitive tool for the electrochemical determination of TR, which exhibited an excellent electrocatalytic activity toward TR oxidation. Electron scanning microscopy, X-ray diffraction measurements (XRD) and differential pulse voltammetry (DPV) were used to characterize the performance and microstructure of the sensor. The electrochemical oxidation of TR was investigated at ZnO/rGO/CPE by f DPV. The developed electrode exhibited an excellent electrochemical activity towards the electrochemical oxidation of TR. Under the optimized experimental conditions, the calibration curve was linear in the range of 0.01–10.0 µmol L⁻¹ with two different slopes and a detection limit (DL) of 2.0 nmol L⁻¹ was obtained. Finally, the electrochemical oxidation of TR at the surface of ZnO/rGO/CPE was employed for the voltammetric determination of TR in serum samples at trace levels with good recoveries.