Hybrid Hydrogels Based on insitu Interpenetrating Networks Graphene Oxide (GO) and Au Nanoparticles, and Its Application as Peroxidase Mimetics for Glucose Detection

Abstract Graphene oxide ( GO ) and Au Nanoparticles (NPs) hybrid hydrogels were prepared through one‐step hydrothermal method. The microstructure of GO/AuNPs hydrogels determined by SEM demonstrated that the hydrogels displayed three‐dimensional (3D) network structure. The freeze‐dried GO/AuNPs hydrogels (xerogels), i. e., GO/Au nanocomposites, could efficiently catalyze the oxidation reaction of peroxidase substrate, 3,3′,5,5′‐tetramethylbenzidine (TMB), in the presence of H 2 O 2 to produce a blue color reaction. Compared with the natural enzyme, horse radish peroxidase (HRP), GO/Au nanocomposites exhibited higher peroxidase‐like activity. The reason might be that the porous 3D network structure of GO/Au nanocomposite enhanced the reaction activity. The catalytic reaction mechanism of GO/Au nanocomposite was followed the Michaelis‐Menten behavior. The combination of GO/Au nanocomposite with glucose oxidase (GOx) performed a selective colorimetric assay for glucose detection with a detection limit of 0.4728 μmol⋅L −1 , which can be used as a promising candidate biosensor for glucose detection.