Ag nanoparticles self-supported on Ag2V4O11 nanobelts: Novel nanocomposite for direct electron transfer of hemoglobin and detection of H2O2

Nanocomposite of Ag nanoparticles self-supproted on Ag2V4O11 nanobelts, prepared by γ-ray irradiation treatments of Ag2V4O11 nanobelts, was used to immobilize hemoglobin on glassy carbon electrode. Detailed electrochemical analysis was performed and it was found that Ag/Ag2V4O11 nanocomposite significantly improved the direct electron transfer between hemoglobin and glassy carbon electrode, leading to the fabrication of a biosensor with a very sensitive detection of H2O2. The apparent surface concentration (Γ*) of hemoglobin and the electron transfer rate constant (ks) were calculated to be 1.6 × 10−10 mol/cm2 and 2.6 s−1, respectively. The linear detection range of H2O2 was 1.0–120 μM, with a detection limit of 0.3 μM.