title: A highly Sensitive Turn-on Fluorescent Sensor for Ba2+Based on G-Quadruplexes.
abstract: A G-quadruplex-based fluorescent biosensor for highly sensitive detection of barium ion (Ba2+) was constructed for the first time. In the absence of Ba2+, the G-quadruplex-specific fluorescence ligand N-methyl mesoporphyrin IX (NMM) remained weakly fluorescent when coexisted with a single-stranded G-quadruplex sequence AGRO100. Upon addition of Ba2+, AGRO100 was folded into G-quadruplex structures with the aid of Ba2+, which bound with NMM by stacking forces and significantly enhanced its fluorescence. The maximum fluorescence intensity of NMM was increased by ca. 22-fold in response to 1 μM Ba2+. This simple method exhibites a good linear relationship in the range of 0-600 nM with the detection limit of 4 nM. The detection method is turn-on, fast, economic, high in signal-to-noise ratio and free of participation of toxic organic solvents, demonstrating its great potential for on-site and real-time Ba2+detection.
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Suzhou, 215123, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Xu
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Suzhou, 215123, China.|School of Pharmacy, Xi'an Jiaotong University, Xi'an, 710061, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Suzhou, 215123, China.|School of Pharmacy, Xi'an Jiaotong University, Xi'an, 710061, China.
authors.forename: Ruihua
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Suzhou, 215123, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Gao
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Suzhou, 215123, China.
authors.forename: Yajie
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Suzhou, 215123, China.
authors.forename: Xiaoqiang
authors.initials: X
authors.lastname: Shen
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Suzhou, 215123, China. rjpei2011@sinano.ac.cn.
authors.forename: Renjun
authors.initials: R
authors.lastname: Pei
keywords: Barium; Fluorescence; G-quadruplexes; Label-free; Sensors