Pb2+-Induced Allosteric PS2.M as A Label-Free Colorimetric Sensor for Detection of Cumulative Radon Radiation
10.11895/j.issn.0253-3820.171151
- VernacularTitle:铅离子诱导PS2.M构象改变特性及其氡非标记比色传感检测新方法
- Author:
Hong-Wen LIU
1
;
Ying JI
;
Chun-Li SONG
;
Gang TIAN
;
Shi-Ya LI
;
Gui-Ying YANG
;
Chang-Yin LYU
Author Information
1. 南华大学公共卫生学院
- Keywords:
Radon;
Lead;
Aptamer;
G-quadruplex;
Conformation transformation;
Colorimetric sensor
- From:
Chinese Journal of Analytical Chemistry
2018;46(5):658-663
- CountryChina
- Language:Chinese
-
Abstract:
A new sensitive method for detection of cumulative radon radiation based on the lead was established. PS2.M which stabilized by K+with hemin as a co-factor exhibits superior peroxidase-like activity, and can effectively catalyze the H2O2-mediated oxidation of TMB. In the presence of Pb2+, K+-stabilized PS2.M DNAzymes are induced to undergo a conformational change,because Pb2+has a higher efficiency with regard to stabilizing G-quadruplexes than K+, accompanied by a decrease of catalytic activity and a sharp decrease of readout signal. In the work, a novel"turn-off"model of colorimetry-Pb2+biosensor based on superior peroxidase-like activity of G-quadruplex for Pb2+analysis was developed. The fading degree of reaction system (△A value) was linearly related to Pb2+concentration in the range of 5. 0×10-9-1. 8× 10-7mol/L. The linear regression equation was △A=0.36+0.13C (10-8mol/L), with R=0.9987. The detection limits of lead and radon were 3.76 nmol/L(S/N=3) and 1.96×103Bq·h/m3(S/N=3), respectively. The method exhibited good selectivity, high sensitivity and convenient operation, and could avoid the radioactive hazard in determination of the radon in environment.
