Copper oxide-carboxylated graphene nanocrystals modified electrode for sensitive detection of glucose

A novel approach for electrochemical detection of glucose has been developed by flower-like copper oxide-carboxylated graphene (CuO-CG) nanocrystals modified electrode. The modified electrode was constructed by the electrodeposition method. CG and copper were successively electrodeposited on a bare glassy carbon electrode (GCE), and then CuO was formed in situ by electrochemical oxidization of the copper film to obtain the final CuO-CG-GCE. Electrocatalytic activity of the CuO-CG-GCE towards glucose oxidation was explored using cyclic voltammetry. The oxidation peak current of glucose obtained by CuO-CG-GCE was more than 130-fold higher than that of the bare GCE. The CuO-CG-GCE could detect glucose from 0.1 μM to 3.17 mM by chronoamperometry with a limit of detection of 10 nM, sensitivity of 1295 μA mM−1 cm−2, and response time of 1 ∼ 4 s. These results suggested that the CuO-CG nanocrystals could become promising electrode materials for electrochemical sensors.