▎ 摘　　要

Direct electrochemistry of glucose oxidase (GOD) was conducted on the surface of a novel graphene-graphene oxide (GR-GO) nanocomposite. GR-GO possesses the virtues of excellent biocompatibility and conductivity, and high sensitivity to local perturbations, and can provide a biocompatible microenvironment for protein immobilization and a suitable electron transfer distance between the electroactive centers of GOD and the electrode surface. The voltammetric results indicated that GOD assembled on GR-GO retained its native structure and bioactivity, exhibited a surface-confined process, and underwent an effective direct electron transfer (DET) reaction with an apparent rate constant (k(s)) of 3.5 s(-1). Furthermore, the proposed biosensor exhibited a wider linear response to glucose concentrations between 0.1 mM and 11 mM, with a detection limit of 20 mu M and a much higher sensitivity (15.85 mu A mM(-1) cm(-2)).