Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7232705 | Biosensors and Bioelectronics | 2015 | 7 Pages |
Abstract
In this study, a novel and ultrasensitive sandwich-type electrochemical immunosensor was prepared for the quantitative detection of alpha fetoprotein (AFP), a well-known hepatocellular carcinoma biomarker. Gold nanoparticles (Au NPs) functionalized magnetic multi-walled carbon nanotubes (MWCNTs-Fe3O4) were prepared and utilized for the adsorption of lead ions (Pb2+) and the secondary antibodies (Ab2). The resultant nanocomposites (Pb2+@Au@MWCNTs-Fe3O4) were used as the label for signal amplification, showing better electrocatalytic activity towards the reduction of hydrogen peroxide (H2O2) than MWCNTs, MWCNTs-Fe3O4 or Au@MWCNTs-Fe3O4 due to the synergetic effect presented in Pb2+@Au@MWCNTs-Fe3O4. Moreover, Au NPs were electrodeposited on the surface of glassy carbon electrode (GCE) for the effective immobilization of primary antibodies (Ab1). Under the optimal conditions, a linear range from 10Â fg/mL to 100Â ng/mL and a detection limit of 3.33Â fg/mL were obtained. The proposed electrochemical sandwich-type immunosensor shows high sensitivity, good selectivity and stability for the quantitative detection of AFP, holding a great potential in clinical and diagnostic applications.
Keywords
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Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Faying Li, Jian Han, Liping Jiang, Yulan Wang, Yueyun Li, Yunhui Dong, Qin Wei,