Self-assembled monolayer assisted binding of partially oxidized graphene on gold: Tunable electron-transfer mediation and in-situ electrochemical disassembly

In this research a class of graphene modified electrodes based on self-assembled monolayer assisted binding of partially oxidized graphene on gold was achieved. The electrodes show two features: (1) the tunable electron-transfer mediation ability which is controlled by the oxidation degree of the graphene, and (2) the ability of in-situ electrochemical disassembly. The tunable electron-transfer mediation ability was investigated by interpreting the cyclic voltammogram recorded with the classic redox couple, potassium ferricyanide/ferrocyanide. The ability of in-situ electrochemical disassembly was investigated by cyclic voltammetry and electrochemical impedance spectroscopy in the case of enzyme adsorption. It was found that the “on” and “off” conditions of the partially oxidized graphene correspond to the assembly and disassembly of the mercaptosuccinic acid self-assembled monolayer respectively, endowing the electrodes with the ability of in-situ electrochemical disassembly. In addition, the experimental results on glucose sensing illustrate the potential applications of the graphene modified electrodes.