title: Electrochemical immunoassay of benzo[a]pyrene based on dual amplification strategy of electron-accelerated Fe3O4/polyaniline platform and multi-enzyme-functionalized carbon sphere label.
abstract: An electrochemical immunosensor, basing on a dual amplification strategy by employing a biocompatible Fe(3)O(4)/polyaniline/Nafion (Fe(3)O(4)/PANI/Nafion) layer as sensor platform and multi-enzyme-antibody functionalized highly-carbonized spheres (multi-HRP-HCS-Ab(2)) as label, was constructed for sensitive detection of benzo[a]pyrene (BaP). The stable film, Fe(3)O(4)/PANI/Nafion, can not only immobilize biomolecules, but also catalyze the reduction of hydrogen peroxide, indicating an accelerated electron transfer pathway of the platform. The experimental conditions, including the concentration of Nafion, concentration of Fe(3)O(4)/polyaniline (Fe(3)O(4)/PANI), pH of the detection solution and concentrations of biomolecules, were studied in detail. Basing on a competitive immunoassay, the current change was proportional to the logarithm of BaP concentration in the range of 8 pM and 2 nM with the detection limit of 4 pM. The proposed immunosensor exhibited acceptable reproducibility and stability. This new type of dual amplification strategy may provide potential applications for the detection of environmental pollutants.
authors.affiliation: Institute of Biomaterials, College of Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, China.
authors.forename: Mouhong
authors.initials: M
authors.lastname: Lin
authors.forename: Yingju
authors.initials: Y
authors.lastname: Liu
authors.forename: Zihong
authors.initials: Z
authors.lastname: Sun
authors.forename: Shenglai
authors.initials: S
authors.lastname: Zhang
authors.forename: Zhuohong
authors.initials: Z
authors.lastname: Yang
authors.forename: Chunlin
authors.initials: C
authors.lastname: Ni
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D055910:Antibodies, Immobilized / Q000276:immunology; D001564:Benzo(a)pyrene / Q000032:analysis*; D055664:Electrochemical Techniques; D004579:Electron Transport; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D005465:Fluorocarbon Polymers / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D055767:Immobilized Proteins / Q000737:chemistry / Q000378:metabolism; D007118:Immunoassay; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D000814:Aniline Compounds; D055910:Antibodies, Immobilized; D005465:Fluorocarbon Polymers; D055767:Immobilized Proteins; D037742:Nanotubes, Carbon; C416807:polyaniline; D001564:Benzo(a)pyrene; C040402:perfluorosulfonic acid; D006735:Horseradish Peroxidase; D052203:Ferrosoferric Oxide