Xu J.,Tyndall National Institute |
Shang F.,Analytical and Biological Chemistry Research Facility ABCRF |
Luong J.H.T.,NRC Biotechnology Research Institute |
Razeeb K.M.,Tyndall National Institute |
Glennon J.D.,Analytical and Biological Chemistry Research Facility ABCRF
Biosensors and Bioelectronics | Year: 2010
Vertically aligned nanowire array electrodes (NAEs) were prepared by electrodeposition of gold into an anodic aluminium oxide membrane (AAM), providing an ordered three-dimensional (3D) matrix for immobilization of redox proteins. Third-generation H2O2 biosensors were prepared by covalent immobilization of horseradish peroxidase (HRP) on the self-assembled monolayer modified NAEs. Direct electron transfer and electrocatalytic performances of the HRP/NAEs with different nanowire lengths (deposition time of 2, 4 and 5 h) were investigated. Results showed that with longer nanowires, better performances were achieved. The HRP/NAE5 h (5 h deposition time) exhibited remarkable sensitivity (45.86 μA mM-1 cm-2) towards H2O2 with a detection limit of 0.42 μM (S/N = 3), linearity up to 15 mM and a response time of 4 s. The ordered 3D gold nanowire array with high conductivity, excellent electron transfer capability and good biocompatibility proved promising for fabricating sensitive, selective, stable and mediator-free enzymatic biosensors. © 2009 Elsevier B.V. All rights reserved.