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

Abstract

AbstractGraphene 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 H2O2 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.