Fabrication of a fast response non-enzymatic glucose sensor based on in-situ synthesized Cu-metal organic frameworks integrated with electrochemically reduced graphene quantum dots

Objective(s): During this study, a novel and fast response platform based on in-situ synthesis of Cu-metal organic frameworks (Cu-MOFs) integrated with electrochemically reduced graphene quantum dots (ErGQDs) was developed through an electrochemical deposition method and a conversation process for non-enzymatic glucose determination.Materials and Methods: In the first step, metallic copper and ErGQDs were simultaneous electrochemically deposited on the surface of carbon ceramic electrode (CCE). Then, metallic copper was converted to copper oxide by cyclic voltammetry technique. Finally, by adding the benzene-1, 3, 5-tricarboxylic acid (BTC), copper-based MOFs was formed on the surface of constructed electrode by an in-situ conversation process and the fabricated electrode (Cu-MOFs/ErGQDs/CCE) was used for the non-enzymatic electrochemical detection of glucose. The physicochemical characterization and electrocatalytic behavior of fabricated electrode toward glucose oxidation were studied through the suitable techniques. Results: The electrochemical results demonstrated that the Cu-MOFs/ErGQDs/CCE is a suitable sensor for glucose determination which exhibits wide linear ranges (2.0-500.0 µM), low detection limit [0.59 µM (S/N=3)], high sensitivity (5069 μA mM-1cm-2), stability (RSD%=3.02), reproducibility (RSD%= 2.09) and good selectivity. Conclusion: Overall, this study highlights the development of Cu-MOFs/ErGQDs/CCE as a sensor with promising characteristics for non-enzymatic determination of glucose. So that, the present sensor was used for detection of glucose in human blood serum and saliva samples.