A glucose biosensor based on cytochrome c and glucose oxidase co-entrapped in chitosan–gold nanoparticles modified electrode

Abstract

A glucose biosensor was developed based on cytochrome c (Cyt c) and glucose oxidase (GOD) co-entrapped on gold nanoparticles (AuNPs)–chitosan (CHIT) nanocomposites which were constructed on glassy carbon electrode (GCE) by one-step electrodeposition. The surrounding Cyt c around GOD provided a biocompatible microenvironment to keep GOD's biological activity. Simultaneously, the AuNPs–CHIT nanocomposites provided a roughened surface with large surface-to-volume ratio to greatly amplify the surface coverage of GOD–Cyt c molecules and good conductivity to realize the direct electron transfer (DET) of GOD. The biosensor showed a wide detection range, low detection limit, good stability and high sensitivity. Thus, this study not only successfully achieved DET of GOD, but also constructed satisfactory point-of-care glucose monitoring.