title: A novel amperometric immunosensor constructed with gold-platinum nanoparticles and horseradish peroxidase nanoparticles as well as nickel hexacyanoferrates nanoparticles.
abstract: In this study, three nano-materials comprising gold-platinum nanoparticles (Au-PtNPs), horseradish peroxidase nanoparticles (HRPNPs) and nickel hexacyanoferrate nanoparticles (NiHCFNPs) were used to construct a signal-off immunosensor. Au-PtNPs and NiHCFNPs were assembled on a glass carbon electrode (GCE) by electrodeposition and gold-cyanide bond formation, respectively; anti-fetoproteins (anti-AFP) were immobilized on the Au-PtNPs. HRPNPs were employed to block the possible remaining active sites and avoid nonspecific adsorption. Here, NiHCFNPs served as redox probes, while Au-PtNPs and HRPNPs were used for the synergistic catalysis of H(2)O(2) to amplify the signal. With more and more immunocomplex produced by the antibody-antigen reaction covering the biosensing surface, thus hindering electron transfer, the catalytic peak current will decrease quantitatively in relation to the concentration of target antigen. The resulting immunosensors exhibited a fast response and excellent sensitivity to α-fetoprotein (AFP), and showed two linear ranges in the concentration ranges of 0.06-13 ng mL(-1) and 13-200 ng mL(-1) with a detection limit of 0.017 ng mL(-1).
authors.affiliation: The Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Southwest University, Chongqing 400715, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhu
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
authors.forename: Jing
authors.initials: J
authors.lastname: Han
authors.forename: Ya
authors.initials: Y
authors.lastname: Li
authors.forename: Ni
authors.initials: N
authors.lastname: Liao
mesh_terms: D000937:Antigen-Antibody Reactions; D015374:Biosensing Techniques; D020134:Catalytic Domain; D055664:Electrochemical Techniques; D004566:Electrodes; D005295:Ferrocyanides / Q000737:chemistry; D006047:Gold Alloys / Q000737:chemistry; D006735:Horseradish Peroxidase; D006861:Hydrogen Peroxide / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry; D010084:Oxidation-Reduction; D010984:Platinum / Q000737:chemistry; D000509:alpha-Fetoproteins / Q000032:analysis* / Q000276:immunology*
chemical_list: D005295:Ferrocyanides; D006047:Gold Alloys; D000509:alpha-Fetoproteins; C116383:ferrocyn; D010984:Platinum; D009532:Nickel; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase