Facile Synthesis and Electrochemical Performance of Graphene-Modified Cu2O Nanocomposite for Use in Enzyme-Free Glucose Biosensor

Graphene-modified Cu2O nanocomposite was synthesized under facile microwave irradiation of an aqueous solution and has been investigated as an enzyme-free glucose biosensor. Morphology and crystal structure of the graphene-modified Cu2O nanocomposite were investigated by using electron microscopy and X-Ray Diffraction (XRD) analyses. Also, the electrochemical performance of the graphene-modified Cu2O nanocomposite for the measurement of glucose concentration in alkaline media was evaluated by using cyclic voltammetry and chronoamperometric measurements. The electrochemical studies revealed that the graphene-modified nanocomposite electrode exhibited a high performance for non-enzymatic oxidation of glucose with a desirable sensitivity. Also, the fabricated graphene-modified biosensor exhibited a wide linear response for glucose detection in the concentrations ranges from 2 µM to 12 mM and a desirable detection limit of 2 µM. Also, the graphene-modified Cu2O nanocomposite provided an appropriate selective response for glucose detection in the presence of high concentrations of ascorbic acid and dopamine.