title: A colorimetric aptasensor for the highly sensitive detection of 8-hydroxy-2'-deoxyguanosine based on G-quadruplex-hemin DNAzyme.
abstract: A highly sensitive, low-cost colorimetric aptasensor was developed for the determination of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in human urine. The method is based on a conformational switching of the 8-OHdG aptamer to form a G-quadruplex structure in the presence of 8-OHdG. The resulting G-quadruplex assembles into a peroxidase-like DNAzyme with hemin, which effectively catalyzes the oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS(2-)) by H2O2 to ABTS(+), resulting in an increase in the absorption signal at 416nm along with a color change of the solution. The response signals linearly correlated with the concentration of 8-OHdG, ranging from 466pM to 247nM with a detection limit of 141pM. The relative standard deviation and the recovery were 1.97-3.47% (n=11) and 98.8-100.2%, respectively. The proposed method avoids the label and derivatization steps in common methods and allows direct analysis of the samples by the naked eye without costly instruments, which is reliable, inexpensive, and sensitive.
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China. Electronic address: yongsheng.w@tom.com.
authors.forename: Yong-Sheng
authors.initials: YS
authors.lastname: Wang
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China; College of Public Health, Dali University, Dali 671000, People's Republic of China.
authors.forename: Jia-Cheng
authors.initials: JC
authors.lastname: Wang
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Jin-Hua
authors.initials: JH
authors.lastname: Xue
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhao
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Shan-Du
authors.initials: SD
authors.lastname: Liu
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Xian
authors.initials: X
authors.lastname: Tang
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Si-Han
authors.initials: SH
authors.lastname: Chen
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Ming-Hui
authors.initials: MH
authors.lastname: Li
authors.affiliation: College of Public Health, University of South China, Hengyang 421001, People's Republic of China.
authors.forename: Jin-Xiu
authors.initials: JX
authors.lastname: Cao
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D052160:Benzothiazoles / Q000737:chemistry; D003124:Colorimetry; D021881:DNA, Catalytic / Q000378:metabolism*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine; D054856:G-Quadruplexes; D006427:Hemin / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D013451:Sulfonic Acids / Q000737:chemistry
chemical_list: D052157:Aptamers, Nucleotide; D052160:Benzothiazoles; D021881:DNA, Catalytic; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D006427:Hemin; D000080242:8-Hydroxy-2'-Deoxyguanosine; D006861:Hydrogen Peroxide; D003849:Deoxyguanosine
keywords: 8-Hydroxy-2′-deoxyguanosine; Colorimetric aptasensor; Conformational switching; G-quadruplex; Hemin