title: Direct growth of nanoporous Au and its application in electrochemical biosensing.
abstract: In this work, we have directly grown three-dimensional nanoporous Au networks onto a Ti substrate using the hydrothermal technique. This newly designed material with a large surface area was used as a supporting matrix for immobilizing a redox protein, hemoglobin (Hb), to develop a high-performance hydrogen peroxide biosensor. Scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray (EDX) spectroscopy were employed to characterize the morphology and composition of the fabricated nanoporous Au network. Cyclic voltammetry (CV) and amperometry were used to study and to optimize the performance of the fabricated electrochemical biosensor. Our CV studies show the direct electron transfer of Hb immobilized on the nanoporous Au network. In addition, amperometric H(2)O(2) sensing experiments revealed that the nanoporous Au-network based biosensor exhibits fast response, long linearity, a low detection limit, high stability and very good reproducibility. Under the optimized conditions, the linearity of the developed biosensor for the detection of H(2)O(2) spans from 5 x 10(-8) to 2 x 10(-4)M with a detection limit of 2 x 10(-8)M (based on S/N=3).
authors.affiliation: Department of Chemistry, Lakehead University, Thunder Bay, Ontario P7B 5E1, Canada.
authors.forename: A K M
authors.initials: AK
authors.lastname: Kafi
authors.forename: Asieh
authors.initials: A
authors.lastname: Ahmadalinezhad
authors.forename: Jingpeng
authors.initials: J
authors.lastname: Wang
authors.forename: Dan F
authors.initials: DF
authors.lastname: Thomas
authors.forename: Aicheng
authors.initials: A
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D006454:Hemoglobins / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation*; D016062:Porosity; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D006454:Hemoglobins; D006046:Gold; D006861:Hydrogen Peroxide