An optionality further amplification of an sandwich-type electrochemical immunosensor based on biotin–streptavidin–biotin strategy for detection of alpha fetoprotein. Issue 29 (3rd March 2016)

• Record Type: Journal Article
• Authors: Jiang, Liping; Li, Faying; Feng, Jinhui; Wang, Ping; Liu, Qing; Li, Yueyun; Dong, Yunhui; Wei, Qin
• Is Part Of: RSC advances. Volume 6:Issue 29(2016)
• Page Start: 24373
• Page End: 24380
• Publication Date: 2016-03-03
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra01178k
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : An optionality further amplification of sandwich-type electrochemical immunosensor based on biotin–streptavidin–biotin strategy. Abstract : An optionality further amplification of sandwich-type electrochemical immunosensor based on Au NPs as platform and biotin-functionalized amination magnetic nanoparticle composite (B-APTES@Fe3 O4 ) as label was designed for detection of alpha fetoprotein (AFP) in this work. The cross-shaped SA has one free biotin-binding site available for carrying a B-Ab2, and the other three binding sites are conjugated with a 3 equimolar ratio of B-APTES@Fe3 O4 . Thus, further signal amplification could be achieved as SA and B-APTES@Fe3 O4 are added layer by layer on the electrode successively. Of the active biotins that were modified on the surface of APTES@Fe3 O4, a part of biotins are bound to the SA and the remaining biotins can be used for further connection, which can present a dendritic spread outward. Therefore, the proposed electrochemical immunosensor has wider application range than before. Under optimal conditions, the designed immunosensor exhibited a wide linear range from 1 pg mL −1 to 10 ng mL −1 with a low detection limit of 0.33 pg mL −1 (S/N = 3) for HIgG. The proposed immunosensor provides a promising application for the quantitative detection of biomolecules in serum samples.