title: A Sensitive and Label-Free Pb(II) Fluorescence Sensor Based on a DNAzyme Controlled G-Quadruplex/Thioflavin T Conformation.
abstract: Pb(II) can cause serious damaging effects to human health, and thus, the study of Pb2+detection methods to sensitively and selectively monitor Pb(II) pollution has significant importance. In this work, we have developed a label-free fluorescence sensing strategy based on a Pb(II) DNAzyme cleavage and the ThT/G-quadruplex complex. In the presence of Pb(II), a G-rich tail was cut and released from the substrate strand, which then would form a G-quadruplex structure by combination with ThT dye. The fluorescence signal increase was then measured for sensitive Pb(II) quantification with a limit of detection of 0.06 nM. Our sensor also demonstrated high selectivity against six different metal ions, which is very important for the analysis of complex samples.
authors.affiliation: Biometrology Laboratory, Division of Chemistry and Ionizing Radiation Measurement Technology, Shanghai Institute of Measurement and Testing Technology, Shanghai 201203, China. wenyl@simt.com.cn.
authors.forename: Yanli
authors.initials: Y
authors.lastname: Wen
authors.affiliation: Biometrology Laboratory, Division of Chemistry and Ionizing Radiation Measurement Technology, Shanghai Institute of Measurement and Testing Technology, Shanghai 201203, China. Wangll@simt.com.cn.
authors.forename: Lele
authors.initials: L
authors.lastname: Wang
authors.affiliation: Biometrology Laboratory, Division of Chemistry and Ionizing Radiation Measurement Technology, Shanghai Institute of Measurement and Testing Technology, Shanghai 201203, China. Lily@simt.com.cn.
authors.forename: Lanying
authors.initials: L
authors.lastname: Li
authors.affiliation: Biometrology Laboratory, Division of Chemistry and Ionizing Radiation Measurement Technology, Shanghai Institute of Measurement and Testing Technology, Shanghai 201203, China. Xuli@simt.com.cn.
authors.forename: Li
authors.initials: L
authors.lastname: Xu
authors.affiliation: Biometrology Laboratory, Division of Chemistry and Ionizing Radiation Measurement Technology, Shanghai Institute of Measurement and Testing Technology, Shanghai 201203, China. liugang0731@gmail.com.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
mesh_terms: D052160:Benzothiazoles; D015374:Biosensing Techniques / Q000295:instrumentation*; D021881:DNA, Catalytic / Q000737:chemistry*; D005453:Fluorescence; D054856:G-Quadruplexes; D007854:Lead / Q000032:analysis*; D057230:Limit of Detection; D008968:Molecular Conformation; D013194:Staining and Labeling; D013696:Temperature; D013844:Thiazoles / Q000737:chemistry*
chemical_list: D052160:Benzothiazoles; D021881:DNA, Catalytic; D013844:Thiazoles; C009462:thioflavin T; D007854:Lead
keywords: DNAzyme; heavy metal ions; lead ion; thioflavin T (ThT)