title: A sandwich-type electrochemical immunosensor based on the biotin- streptavidin-biotin structure for detection of human immunoglobulin G.
abstract: A sandwich-type immunosensor is designed and fabricated to detect the human immunoglobulin G (HIgG) using polyaniline and tin dioxide functionalized graphene (GS-SnO2-PAN) as the platform and biotin-functionalized amination magnetic nanoparticles composite (B-Fe3O4@APTES) as the label. GS-SnO2-PAN is used as the sensing agent to capture the primary anti-HIgG (Ab1) and SnO2 reduces the stack of GS. The B-Fe3O4@APTES with a large surface area and excellent biocompatibility captures second antibody (Ab2) efficiently based on the highly selective recognition of streptavidin to biotinylated antibody. The B-Fe3O4@APTES has better electro-catalytic activity in the reduction of hydrogen peroxide (H2O2) and the "biotin-streptavidin-biotin" (B-SA-B) strategy leads to signal amplification. Under optimal conditions, the immunosensor has a wide sensitivity range from 1 pg/L to 10 ng/L and low detection limit of 0.33 pg/L (S/N = 3) for HIgG. The immunosensor has high sensitivity, fast assay rate, as well as good reproducibility, specificity, and stability especially in the quantitative detection of biomolecules in serum samples.
authors.affiliation: Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing, 100083, P. R. China.|School of Chemical Engineering, Shandong University of Technology, Zibo, 255049, P. R. China.
authors.forename: Yueyun
authors.initials: Y
authors.lastname: Li
authors.affiliation: Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing, 100083, P. R. China.
authors.forename: Yihe
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, Zibo, 255049, P. R. China.
authors.forename: Liping
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Department of Physics &Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
authors.forename: Paul K
authors.initials: PK
authors.lastname: Chu
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, Zibo, 255049, P. R. China.
authors.forename: Yunhui
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, P.R. China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D001710:Biotin / Q000378:metabolism; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D007202:Indicators and Reagents / Q000378:metabolism; D008280:Magnetics; D053758:Nanoparticles; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019809:Streptavidin / Q000378:metabolism
chemical_list: D007074:Immunoglobulin G; D007202:Indicators and Reagents; D001710:Biotin; D019809:Streptavidin