Cobalt oxide nanoparticles electrodeposited on glassy carbon electrode for metronidazole determination

Abstract

Herein, we introduced a sensing platform for the electrochemical determination of metronidazole (MTZ) via a modified glassy carbon electrode (GCE) by cobalt oxide nanoparticles (CoOX NPs). Co NPs were deposited onto GCE in a solution containing CoSO4 and Na2SO4 by repetitive potential cycling. In the next step, the modified electrode was positioned in a hydroxide solution and scanned repetitively to stabilize and activate the Co NPs. The surface morphology of the CoOX NPs onto the GCE was characterized by energy dispersive X-ray (EDX) spectroscopy and scanning electron microscopy (SEM). The electrochemical activity of the modified electrode towards the reduction of MTZ was studied by differential pulse voltammetry (DPV) and cyclic voltammetry (CV). The peak current showed a linear response to MTZ concentration from 6.95 to 982.98 µM, with a limit of detection of 3.12 µM (S/N = 3), using differential pulse voltammetry. The proposed assay was applied for the analysis of MTZ in medicinal samples.

Keywords

• Glassy carbon electrode
• Cobalt oxide nanoparticles
• Metronidazole
• Cyclic voltammetry