▎ 摘　　要

A sensitive and selective amperometric H2O2 biosensor was obtained by utilizing the electrodeposition of Pt flowers on iron oxide-reduced graphene oxide (Fe3O4/rGO) nanocomposite modified glassy carbon electrode (GCE). The morphology of Fe3O4/rGO and Pt/Fe-3 O-4/rGO was characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. The step-wise modification and the electro-chemical characteristics of the resulting biosensor were characterized by cyclic voltammetry (CV) and chronoamperometry methods. Thanks to the fast electron transfer at the Pt/Fe3O4/rGO electrode interface, the developed biosensor exhibits a fast and linear amperometric response upon H2O2. The linear range of Pt/Fe3O4/rGO is 0.1 similar to 2.4 mM (R-2 = 0.998), with a sensitivity of 6.875 mu A/ mM and a detection limit of 1.58 mu M (S/N-3). In addition, the prepared biosensor also provides good anti-interferent ability and long-term stability due to the favorable biocompatibility of the electrode interface. The proposed sensor will become a reliable and effective tool for monitoring and sensing the H2O2 in complicate environment.