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Indexed by:期刊论文

Date of Publication:2015-01-01

Journal:TALANTA

Included Journals:SCIE、EI、PubMed

Volume:131

Page Number:379-385

ISSN No.:0039-9140

Key Words:Core-shell nanoparticle; 8-hydroxy-2 '-deovguanosine; Electrochemiluminescence immnuosensor; Carbon quantum dot

Abstract:An electrochemiluminescence (ECL) immunosensor using Pt electrode modified with carbon quantum dot (CQDs) coated Au/SiO2 core-shell nanoparticles was proposed for sensitive detection of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in this work. Rabbit anti-8-OHdG antibody was covalently bound to CQDs on the surface of Au/SiO2 core-shell nanoparticles. Through signal amplification of Au/SiO2 core-shell nanoparticles, 8-fold enhancement of the ECL signals was achieved. Under optimal conditions, a good linear range from 0.2 to 200 ng mL(-1) with a low detection limit of 0.085 ng mL(-1) (S/N=3) for 8-OHdG detection was obtained. Interfering substances tests showed that the corresponding ECL intensity (Delta ECL) of 8-OHdG is 8-18 times higher than that of guanine, uric acid (UA) and ascorbic acid, demonstrating its good selectivity for 8-OHdG detection. The ECL immnuosensor exhibits long-term stability with a relative standard deviation (RSD) of 8.5% even after 16 cycles of continuous potential scans. The result of analytical detection of 8-OHdG in real samples was satisfactory. The proposed ECL immnuosensor shows good performance with high sensitivity, specificity, repeatability, stability and provided a powerful tool for 8-OHdG monitoring in clinical samples. (C) 2014 Elsevier B.V. All rights reserved.