A high-performance Co-MOF non-enzymatic electrochemical sensor for glucose detection

Abstract

Two cobalt metal–organic frameworks (Co-MOFs), [Ch]₂[Co₃(BDC)₃Cl₂] (1) and [Ch]₂[Co₃(BDC)₄]·2DMU (2) (Ch⁺ = choline cation; H₂BDC = terephthalic acid; DMU = 1,3-dimethylurea), were prepared through ionothermal reactions with deep eutectic solvents (DESs) of ChCl and DMU as the reaction media. The 1/GCE electrode with better current response was selected as the electrocatalyst. The detection performance of the 1/GCE electrode towards glucose is excellent with a wide linear range of 10–1200 μmol L⁻¹, a detection limit of 3.2 μmol L⁻¹ (S/N = 3), and a rapid response less than 3 s in 0.01 mol L⁻¹ NaOH. 1 also exhibits high anti-interference with the existence of D-Man, D-Fru, DL-AA, and BA, long-term stability of 15 days and reproducibility for glucose detection. 1 was utilized to detect glucose in human serum and orange juice. The found glucose concentrations are very close to the added glucose concentrations in the selected situations with low RSD and high recoveries. This demonstrates that as a non-enzymatic glucose sensor, 1/GCE can detect glucose with high accuracy and reliability in different environments.