title: Amperometric bioaffinity sensing platform for avian influenza virus proteins with aptamer modified gold nanoparticles on carbon chips.
abstract: A sandwich assay platform involving a surface formed aptamer-protein-antibody complex was developed to obtain the highly selective and sensitive amperometric detection of H5N1 viral proteins using a gold nanoparticle (NP) modified electrode. This is the first aptamer-antibody pairing reported for the selective detection of H5N1. Nanoparticle deposited screen-printed carbon electrodes were first functionalized by the covalent immobilization of a DNA aptamer specific to H5N1 followed by the adsorption of H5N1 protein. Alkaline phosphatase (ALP) conjugated monoclonal antibody was then adsorbed to form a surface bound Au NPs-aptamer/H5N1/antiH5N1-ALP sandwich complex which was further reacted with the enzyme substrate, 4-amino phenyl phosphate (APP). The current associated with the electrocatalytic reaction of the surface bound ALP with APP increased as the H5N1 concentration increased. A lowest detectable concentration of 100 fM was obtained with a linear dynamic range of 100 fM to 10 pM using differential pulse voltammetry. As an example, the biosensor was applied to the detection of H5N1 protein in diluted human serum samples spiked with different concentrations of the viral protein target.
authors.affiliation: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, 80 Daehakro, Buk-gu, Daegu-city 702-701, Republic of Korea.
authors.forename: Farhana Sharmin
authors.initials: FS
authors.lastname: Diba
authors.affiliation: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, 80 Daehakro, Buk-gu, Daegu-city 702-701, Republic of Korea.
authors.forename: Suhee
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, 80 Daehakro, Buk-gu, Daegu-city 702-701, Republic of Korea. Electronic address: hyejinlee@knu.ac.kr.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Lee
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques; D002244:Carbon / Q000737:chemistry; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004566:Electrodes; D004867:Equipment Design; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype / Q000302:isolation & purification*; D007251:Influenza, Human / Q000097:blood / Q000175:diagnosis*; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*
chemical_list: D055910:Antibodies, Immobilized; D052157:Aptamers, Nucleotide; D002244:Carbon; D006046:Gold
keywords: Au nanoparticle deposition; Biofunctionalized electrode; DNA aptamer; Electrochemical detection; H5N1 detection; Surface sandwich assay