title: Electrochemiluminescence immunosensor for highly sensitive detection of 8-hydroxy-2'-deoxyguanosine based on carbon quantum dot coated Au/SiO2 core-shell nanoparticles.
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 (ΔECL) 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 immunosensor 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 immunosensor shows good performance with high sensitivity, specificity, repeatability, stability and provided a powerful tool for 8-OHdG monitoring in clinical samples.
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China. Electronic address: zhaohuim@dlut.edu.cn.
authors.forename: Hui-Min
authors.initials: HM
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Xin-Fei
authors.initials: XF
authors.lastname: Fan
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Chen
authors.affiliation: Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Xie
authors.initials: X
authors.lastname: Quan
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D015374:Biosensing Techniques / Q000379:methods; D002244:Carbon / Q000737:chemistry*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000032:analysis; D055664:Electrochemical Techniques / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D008892:Milk / Q000737:chemistry; D045663:Quantum Dots; D011817:Rabbits; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D002244:Carbon; D006046:Gold; D012822:Silicon Dioxide; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine
keywords: 8-hydroxy-2′-deoxyguanosine; Carbon quantum dot; Core–shell nanoparticle; Electrochemiluminescence immnuosensor