A simple fabrication of Ag-nanowires@TiO2 core-shell nanostructures for the construction of mediator-free biosensor

One-dimensional Ag-nanowires@TiO2 core-shell nanostructures (ANTNs) have been synthesized via a simple solvent thermal method and employed to immobilize hemoglobin (Hb) in order to fabricate a mediator-free biosensor. Immobilized Hb on ANTNs protected by nafion film exhibited good bioactivity, stability, and remarkable electron transfer rate because of its unique core-shell structure and compose. The morphology and structure of the ANTNs were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Electrochemical measurements revealed that the ANTNs were an immobilization support with biocompatibility for enzymes, affording good enzyme stability and bioactivity. Due to the unique Ag-nanowires@TiO2 core-shell nanostructures, the resulting biosensor displayed good performance for the detection of H2O2, with both a low detection limit of 1.3 μM and a wide linear range of 4–152 μM, as well as a fast response and excellent long-term stability.