Abstract: Enzyme, produced and worked in all living things, could work as macromolecular biological catalysts in diverse biochemical processes with particular specificity, like glucose oxidase (GO_X). The efficient use of enzyme properties has great importance in pharmaceutics and therapeutics. In this work, we could fabricate naive and effective electrochemical biosensors in the determination of glucose levels via utilizing GO_X. Graphene oxide, as a water-soluble derivative of graphene, has shown great promise in a variety of biomedical applications including biosensors. Thus, we established a new-type special platform for GO_X immobilization to perform its prosperities, in which nanographene oxide (nGO) was employed as an ideal base and poly(ethylene glycol) (PEG) was conjugated on the edge of nGO sheets to enhance its biocompatibility. Additionally, preferable functional dyes (Rhodamine B/fluorescein isothiocyanate) were also introduced to the platform. Enzyme-nanocomposites were then provided by locating GO_X on the platform, i.e., GO_X@nGO-PEG-RhB and GO_X@nGO-PEG-FITC. The microstructure and composite of platforms and enzyme-nanocomposites were confirmed by diverse characterizations. Finally, on account of corresponding cyclic voltammetric and typical ready-state amperometric curves, it was informed that GO_X@nGO-PEG-RhB and GO_X@nGO-PEG-FITC could effectively respond to the fluctuation of glucose level as electrochemical biosensor. The present work presents special platforms for the immobilization of enzymes like GO_X and provides new-type biosensors in the detection of glucose levels.

Key words: Nanographene oxide, GO_X, Fluorescence dye, Sensor, Glucose