1. Sandwich-type electrochemical immunosensor using dumbbell-like nanoparticles for the determination of gastric cancer biomarker CA72-4.
- Author
-
Wu D, Guo Z, Liu Y, Guo A, Lou W, Fan D, and Wei Q
- Subjects
- Antibodies, Immobilized, Carbon chemistry, Electrodes, Ethylenediamines chemistry, Humans, Hydrogen Peroxide chemistry, Limit of Detection, Metal Nanoparticles chemistry, Metal Nanoparticles ultrastructure, Stomach Neoplasms blood, Stomach Neoplasms immunology, Antigens, Tumor-Associated, Carbohydrate blood, Biomarkers, Tumor blood, Biosensing Techniques, Electrochemical Techniques, Immunoassay, Stomach Neoplasms diagnosis
- Abstract
A novel and sensitive nonenzymatic sandwich-type electrochemical immunosensor for the detection of gastric cancer biomarker CA72-4 was fabricated using dumbbell-like PtPd-Fe3O4 nanoparticles (NPs) as a novel kind of label. The signal amplification strategy, using the synergetic effect present in PtPd-Fe3O4 to increase the reduction ability of the NPs toward H2O2, improved the sensitivity of the immunosensor. The immunosensor was constructed by modifying glassy carbon electrode with reduced graphene oxide-tetraethylene pentamine (rGO-TEPA) for effective immobilization of primary anti-CA72-4 antibody (Ab1). Secondary anti-CA72-4 antibody (Ab2) was adsorbed onto the PtPd-Fe3O4 NPs. The proposed immunosensor displayed a wide linear range (0.001-10 U/mL) with the low detection limit (0.0003 U/mL). The immunosensor was evaluated for serum samples, receiving satisfactory results. Therefore, the immunosensor possesses excellent clinical value in cancer screening as well as convenient point-of-care diagnostics., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2015
- Full Text
- View/download PDF