A graphene-modified Co-BDC metal-organic frameworks (Co-MOF) for electrochemical non-enzymatic glucose sensing

Abstract

Abstract In this work, a metal-organic framework (MOF) based on cobalt was decorated with graphene and used as a sensing material for glucose determination with electrochemical principles. The selection of Co-MOF material is based on its porous nature, large surface area, and excellent electrochemical properties. The combination of Co-MOF with graphene (high conductivity) effectively increased the electrochemical sensor current. The fabricated composite owned the good crystallinity with graphene particles attached to the Co-MOF surface. The biosensing performance was evaluated by cyclic voltammetry (CV) with 0.1 M NaOH solution as the bolstering electrolyte. The electrochemical measurement indicated that the prepared materials possessed a well-moved transfer electron between the electrode surface and electrolyte solution. The Co-BDC-3Gr sample obtained the best electrochemical performance with the lowest limit of detection (LOD) of 5.39 μM and the highest sensitivity of 100.49 μA mM-1 cm-2. The selectivity test of the modified Co-MOF was done by comparing the response with other compounds such as dopamine, uric acid, and NaCl. The acquired biosensor had excellent stability, with 93% of the initial response after 30 days of storage.