Ultrasensitive and highly stable nonenzymatic glucose sensor by a CuO/graphene-modified screen-printed carbon electrode integrated with flow-injection analysis

We report here a nonenzymatic glucose sensor based on a CuO/graphene-modified screen-printed carbon electrode (CuOG-SPCE) integrated with flow-injection analysis (FIA). The highly active CuOG-SPCE with well-dispersed CuO nanoparticles on graphene surfaces performed excellent electrocatalytic oxidation of glucose. Under optimal FIA conditions, the proposed biosensor can be employed in the quantification of glucose with the linear range from 0.122 μM to 0.5 mM, the desirable sensitivity up to 2367 μA mM^-1 cm^-2 and the ultralow detection limit of 34.3 nM (S/N = 3) simultaneously. Good repeatability of 1.92% (n = 30) and less effects of common interfering species including ascorbic acid, uric acid, dopamine, fructose, lactose and sucrose were also demonstrated. The CuO-SPCE with highly sensitive, selective and stable consecutive monitoring (t = 1 h) of glucose is promising for the development of an advanced nonenzymatic glucose sensor device.