Label-free fluorescent sensor for lead ion detection based on lead(II)-stabilized G-quadruplex formation.
A label-free fluorescent DNA sensor for the detection of lead ions (Pb(2+)) based on lead(II)-stabilized G-quadruplex formation is proposed in this article. A guanine (G)-rich oligonucleotide, T30695, was used as a recognition probe, and a DNA intercalator, SYBR Green I (SG), was used as a signal reporter. In the absence of Pb(2+), the SG intercalated with the single-stranded random-coil T30695 and emitted strong fluorescence. While in the presence of Pb(2+), the random-coil T30695 would fold into a G-quadruplex structure and the SG could barely show weak fluorescence, and the fluorescence intensity was inversely proportional to the involving amount of Pb(2+). Based on this, a selective lead ion sensor with a limit of detection of 3.79 ppb (parts per billion) and a detection range from 0 to 600 ppb was constructed. Because detection for real samples was also demonstrated to be reliable, this simple, low-cost, sensitive, and selective sensor holds good potential for Pb(2+) detection in real environmental samples.
School of Environmental Science and Engineering, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, and Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Shenshan
S
Zhan
School of Environmental Science and Engineering, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, and Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Yuangen
Y
Wu
School of Environmental Science and Engineering, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, and Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Yanfang
Y
Luo
School of Environmental Science and Engineering, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, and Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Le
L
Liu
School of Environmental Science and Engineering, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, and Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Lan
L
He
School of Environmental Science and Engineering, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, and Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Haibo
H
Xing
School of Environmental Science and Engineering, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, and Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China. Electronic address: zhoupei@sjtu.edu.cn.
Pei
P
Zhou
D001483:Base Sequence; D052160:Benzothiazoles; D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000737:chemistry / Q000235:genetics; D003959:Diamines; D004785:Environmental Pollutants / Q000032:analysis* / Q000737:chemistry* / Q000494:pharmacology; D005456:Fluorescent Dyes / Q000737:chemistry*; D054856:G-Quadruplexes / Q000187:drug effects; D007700:Kinetics; D007854:Lead / Q000032:analysis* / Q000737:chemistry* / Q000494:pharmacology; D009930:Organic Chemicals / Q000737:chemistry; D011804:Quinolines
D052160:Benzothiazoles; D003959:Diamines; D004785:Environmental Pollutants; D005456:Fluorescent Dyes; D009930:Organic Chemicals; D011804:Quinolines; C098022:SYBR Green I; D007854:Lead; D004247:DNA
Fluorescent sensor; G-quadruplex; Lead ion detection