title: Horseradish peroxidase functionalized gold nanorods as a label for sensitive electrochemical detection of alpha-fetoprotein antigen.
abstract: In this study, a novel tracer, horseradish peroxidase (HRP) functionalized gold nanorods (Au NRs) nanocomposites (HRP-Au NRs), was designed to label the signal antibodies for sensitive electrochemical measurement of alpha-fetoprotein (AFP). The preparation of HRP-Au NRs nanocomposites and the labeling of secondary antibody (Ab2) were performed by one-pot assembly of HRP and Ab2 on the surface of Au NRs. The immunosensor was fabricated by assembling carbon nanotubes (CNTs), Au NRs, and capture antibodies (Ab1) on the glassy carbon electrode. In the presence of AFP antigen, the labels were captured on the surface of the Au NRs/CNTs via specific recognition of antigen-antibody, resulting in the signal intensity being clearly increased. Differential pulse voltammetry (DPV) was employed to record the response signal of the immunosensor in phosphate-buffered saline (PBS) containing hydrogen peroxide (H2O2) and 3,3',5,5'-tetramethylbenzidine (TMB). Under optimal conditions, the signal intensity was linearly related to the concentration of AFP in the range of 0.1-100 ng ml(-1), and the limit of detection was 30 pg ml(-1) (at signal/noise [S/N] = 3). Furthermore, the immunoassay method was evaluated using human serum samples, and the recovery obtained was within 99.0 and 102.7%, indicating that the immunosensor has potential clinical applications.
authors.affiliation: Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, and Anhui Key Laboratory of Chem-Biosensing, Anhui Normal University, Wuhu 241000, People's Republic of China.
authors.forename: Jinjin
authors.initials: J
authors.lastname: Guo
authors.affiliation: Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, and Anhui Key Laboratory of Chem-Biosensing, Anhui Normal University, Wuhu 241000, People's Republic of China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Han
authors.affiliation: Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, and Anhui Key Laboratory of Chem-Biosensing, Anhui Normal University, Wuhu 241000, People's Republic of China.
authors.forename: Junchun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, and Anhui Key Laboratory of Chem-Biosensing, Anhui Normal University, Wuhu 241000, People's Republic of China.
authors.forename: Junqing
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, and Anhui Key Laboratory of Chem-Biosensing, Anhui Normal University, Wuhu 241000, People's Republic of China.
authors.forename: Zilin
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, and Anhui Key Laboratory of Chem-Biosensing, Anhui Normal University, Wuhu 241000, People's Republic of China. Electronic address: zhyz65@mail.ahnu.edu.cn.
authors.forename: Yuzhong
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry / Q000276:immunology; D001560:Benzidines / Q000737:chemistry; D055664:Electrochemical Techniques; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D007118:Immunoassay; D057230:Limit of Detection; D043942:Nanotubes / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry; D000509:alpha-Fetoproteins / Q000032:analysis* / Q000276:immunology
chemical_list: D055910:Antibodies, Immobilized; D001560:Benzidines; D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D000509:alpha-Fetoproteins; C021758:3,3',5,5'-tetramethylbenzidine; D006046:Gold; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase
keywords: Alpha-fetoprotein; Carbon nanotubes; Differential pulse voltammetry; Gold nanorods; Immunosensor