Synthesis of cobalt oxide nanoparticles using Cirsium vulgare leaves extract and evaluation of electrocatalytic effects on oxidation of l-cysteine

Abstract

In this present study, cobalt oxide nanoparticles (Co3O4 NPs) were synthesized using Cirsium vulgare leaves extract and characterized using various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). These methods confirmed the formation of Co3O4 NPs, and the microscopic technique confirmed the size of the Co3O4 NPs is about 20 nm. Also, a novel modified electrode for determination of l-cysteine was described by carbon paste electrode modified with Co3O4 NPs (CPE/Co3O4 NPs). The presence of Co3O4 NPs markedly enhances the electrocatalytic activity for determination of l-cysteine. Under the selected conditions, the anodic peak current was linearly dependent on the concentration of l-cysteine in the range 0.20–75 μM by the amperometric method. The detection limit (S/N = 3) was also estimated to be 0.07 μM. This modified electrode was a simple, rapid, and effective sensor, and it was successfully applied to determine of l-cysteine in real samples.