Fabrication of a novel hydrogen peroxide biosensor based on Au-(PEO106PPO70PEO106) hairy nanospheres

In this case, the Au-F127 (triblock copolymer PEO106PPO70PEO106, PEO is short for polyethylene oxide and PPO is the abbreviation of polypropene oxide) hybrid hairy nanospheres were obtained by the redox reaction using pluronic F127 and HAuCl4 as precursor. A novel hemoglobin (Hb) biosensor was fabricated by immobilizing the Hb onto the Au-F127 film on the surface of glassy carbon electrode (GCE). The Au-F127 nanocomposites and Hb were characterized by transmission electron microscopy (TEM), polycrystalline electron diffraction ring pattern and ultra-violet visible spectra (UV–vis). UV–vis spectra suggested that Hb in the film could keep its native secondary structure. The performances of Hb/(Au-F127) on GCE were characterized with cyclic voltammetry (CV) and typical amperometric response (i–t) measurements. The immobilized Hb maintained its bioactivity and displayed an excellent electrochemical behavior with a formal potential of −339 mV. The resulting electrode showed an electrocatalytic activity to hydrogen peroxide (H2O2). The linear response range of the H2O2 biosensor was from 3.0 × 10−7 to 5.7 × 10−4 M with a low detection limit of 4.0 × 10−8 M.