A Non–Enzymatic Electrochemical Sensor of Cu@Co–MOF Composite for Glucose Detection with High Sensitivity and Selectivity

Abstract

A 3D cobalt metal–organic framework (Co–MOF), [Co3(BDC)3(DMU)2], was utilized to prepare Cu@Co–MOF composite in a deposition–reduction process. Cu@Co–MOF/GCE (GCE = glassy carbon electrode) electrode was prepared by “drop–coating” method. Cu@Co–MOF/GCE shows excellent electrocatalytic activity for Glu detection. The chronoamperometric response of Cu@Co–MOF/GCE to Glu concentration (CGlu) displays linear relationships in two CGlu sections with calculated sensitivities of 282.89 μA mM−1 cm−2 within 0.005–0.4 mM Glu and 113.15 μA mM−1 cm−2 within 0.4–1.8 mM Glu. The detection limit is calculated as 1.6 μM at S/N = 3. Cu@Co–MOF/GCE also exhibits a rapid current response, high anti–interference, stability, and repeatability to Glu detection. Cu@Co–MOF/GCE was applied to detect Glu in human serum and orange juice. All found CGlu are very close to those added CGlu with low RSDs and high recoveries. Cu@Co–MOF/GCE as a non–enzymatic electrochemical sensor of Glu has high sensitivity, selectivity, accuracy, and reliability.