Glassy carbon electrode anchored with green zinc oxide nanoparticles derived from Mango peel extract for voltammetric uric acid sensing
摘要
Mango peel extract was utilized for the fabrication of green zinc oxide nanoparticles (gZnO), exploited as a natural stabilizing and reducing agent. X-ray diffraction pattern confirmed the wurtzite crystalline phase with an average crystallite size of 12 nm. The scanning electron microscope observation revealed a spherical-like morphology of gZnO. The electrochemical behavior and EASA of bare and modified GCE were examined using cyclic voltammetry technique. The EASA of bare GCE increased from 0.118 cm2 to 0.182 cm2 after modification with gZnO. Measurement of uric acid (UA) using differential pulse voltammetry (DPV) in 0.1 M phosphate buffer pH 7.0, reveals a sharp oxidation peak at a potential of − 0.08 V (vs. Ag/AgCl). In addition, the UA peak current response was elevated 2.6-fold (from 3.7 µA to 9.75 µA) when analyzed at gZnO/GCE in comparison with bare GCE. The proposed electrode exhibits a narrow linear range at UA concentrations from 0.3 µM to 1.20 µM, with a low LOD value of 0.23 µM. These findings highlight the synergistic interaction between gZnO nanostructure and the conductive carbon matrix, enabling improved sensitivity and electron transfer kinetics. The gZnO/GCE platform offers a green, cost-effective, and non-enzymatic approach for UA detection in low-volume biological samples.