Surface nanocrystallization of glassy carbon electrode: Application in direct electrochemistry of glucose oxidase

The surface nanocrystallization of glassy carbon (GC) electrode was carried out using cyclic voltammetry in anhydrous dimethylformamide containing 0.05 M tetra-n-butylammonium bromine, and carbon nanoparticles with diameter of 10–40 nm were formed on the electrode surface. Comparing with the typical GC electrode, the surface-nanocrystalline GC (SNGC) electrode showed higher electrocatalytic activity for direct electrochemistry of glucose oxidase (GOD) due to higher proportion of edge sites presented on the surface of the SNGC electrode. Because of the surface nanocrystallization of the electrode, a pair of well-defined and quasi-reversible redox peaks of the immobilized GOD was observed for the first time on the GC electrode.