Enhanced Performance of Bioelectrodes Made with Amination-Modified Glucose Oxidase Immobilized on...

This research reveals the improved performance of bioelectrodes made with amination-modified glucose oxidase (GOx-NH₂) and carboxyl-functionalized mesoporous carbon (OMC-COOH). Results showed that when applied with 10 mM EDC amination, the functional groups of NH₂ were successfully added to GOx, according to the analysis of ¹H-NMR, elemental composition, and FTIR spectra. Moreover, after the aminated modification, increased enzyme immobilization (124.01 ± 1.49 mg GOx-NH₂/g OMC-COOH; 2.77-fold increase) and enzyme activity (1.17-fold increase) were achieved, compared with those of non-modified GOx. Electrochemical analysis showed that aminated modification enhanced the peak current intensity of Nafion/GOx-NH₂/OMC-COOH (1.32-fold increase), with increases in the charge transfer coefficient α (0.54), the apparent electron transfer rate constant k (2.54 s^-1), and the surface coverage Γ (2.91 × 10^-9 mol·cm^-2). Results showed that GOx-NH₂/OMC-COOH exhibited impressive electro-activity and a favorable anodic reaction.