Reduced graphene oxide nanosheets decorated with cobalt oxide nanoparticles: A nonenzymatic electrochemical approach for glucose detection

The enormous demand for daily diagnosis of glucose has encouraged the quest for rapid, reliable, and low-cost glucose detection strategies. In this work, the synergic effect of cobalt oxide (Co3O4) nanoparticles and reduced graphene oxide (rGO) nanosheets were used for electrocatalytic oxidation of glucose on glassy carbon electrodes (GCE). The synthesized nanocomposite was fully characterized using X-ray diffractometry, Fourier transform infrared spectroscopy (FTIR), UV-vis spectroscopy, field emission scanning electron microscopy (FE-SEM) with elemental analysis and dynamic light scattering (DLS). The electrochemical performance of the rGO/Co3O4 nanoparticle-modified electrode for enzyme-free detection of glucose was evaluated using cyclic voltammetry (CV). The developed sensor showed an excellent sensitivity towards glucose with the limit of detection (LOD) as low as 3.6 nM in low response time (5 s). The ability of the developed sensor for the detection of glucose in real sample analysis confirmed its potential application in rapid and accurate daily diagnosis of glucose.