title: A label-free DNAzyme fluorescence biosensor for amplified detection of Pb(2+)-based on cleavage-induced G-quadruplex formation.
abstract: DNAzyme-based catalytic beacons have been widely studied for both in vivo and in vitro molecular detection. However, only a few label-free catalytic beacons with excellent analytical performance have been reported so far. In this work, by combining a catalytic DNAzyme for amplified sensing through enzymatic turnover with cleavage-induced G-quadruplex formation, a label-free DNAzyme biosensor was developed for amplified "turn-on" fluorescence detection of Pb(2+) with a detection limit of 3nM. The method is very competitive compared to many other labeled or label-free methods with or without signal amplification. Due to the inherent specificity of the GR-5 DNAzyme, the method also exhibits excellent selectivity. This biosensor successfully detected Pb(2+) in river water samples with high sensitivity and selectivity. Such a method might provide a universal DNAzyme-based sensing platform for sensitive detection of various targets both in environmental and biomedical fields.
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Ting
authors.initials: T
authors.lastname: Fu
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Songlei
authors.initials: S
authors.lastname: Ren
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Liang
authors.initials: L
authors.lastname: Gong
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Hongmin
authors.initials: H
authors.lastname: Meng
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Liang
authors.initials: L
authors.lastname: Cui
authors.affiliation: The Key Laboratory of Life-Organic Analysis, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong 273165, PR China. Electronic address: kongrongmei@126.com.
authors.forename: Rong-Mei
authors.initials: RM
authors.lastname: Kong
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China. Electronic address: xbzhang@hnu.edu.cn.
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Zhang
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
mesh_terms: D001483:Base Sequence; D055162:Biocatalysis; D015374:Biosensing Techniques / Q000379:methods*; D021881:DNA, Catalytic / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D054856:G-Quadruplexes; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis* / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry
chemical_list: D021881:DNA, Catalytic; D014867:Water; D008628:Mercury
keywords: Biosensor; DNAzyme; Fluorescence; G-quadruplex; label-free