▎ 摘　　要

Bimetallic nanoparticles (NPs) in several instances have resulted in improved catalytic properties when compared to the monometallic analogues. This paper reports on a wet-chemistry approach for the synthesis of reduced graphene oxide (rGO) nanosheets decorated with bimetallic Cu-Ag NPs. The nanocomposite possesses the advantages of combining rGO and metallic NPs and exhibits excellent intrinsic peroxidase like activity, which can be used to catalyse the reaction of peroxidase substrates such as 3,3',5,5'-tetramethylbenzidine (TMB) in presence of hydrogen peroxide (H2O2). A combination of the peroxidase-like activity of the Cu-Ag/rGO nanostructures with glucose oxidase ( GluO(x)), allowed the construction of a sensitive and a selective colorimetric assay for glucose detection in blood serum with a detection limit of 3.8 mu M. The monometallic analogues displayed a detection limit of 7.9 mu M (Ag/rGO) and 9.7 mu M (Cu/rGO). In addition, the Cu-Ag/rGO nanostructures were also successfully applied for sensing ascorbic acid with a detection limit of 3.6 mu M. (C) 2016 Elsevier B.V. All rights reserved.