Ag nanoparticles self-supported on Ag 2V 4O 11 nanobelts: Novel nanocomposite for direct electron transfer of hemoglobin and detection of H 2O 2

Abstract

Nanocomposite of Ag nanoparticles self-supproted on Ag 2V 4O 11 nanobelts, prepared by γ-ray irradiation treatments of Ag 2V 4O 11 nanobelts, was used to immobilize hemoglobin on glassy carbon electrode. Detailed electrochemical analysis was performed and it was found that Ag/Ag 2V 4O 11 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 H 2O 2. The apparent surface concentration ( Γ*) of hemoglobin and the electron transfer rate constant ( k s) were calculated to be 1.6 × 10 −10 mol/cm 2 and 2.6 s −1, respectively. The linear detection range of H 2O 2 was 1.0–120 μM, with a detection limit of 0.3 μM.