基于金纳米聚集-核酸适配体传感光度法检测铅  

Spectrophotometric detection of lead ions based on gold nano-aggregation nucleic acid adaptor sensor

作　　者：林永青 李诗雅[1] 杨桂英[1] 刘士蒙 刘然 吕昌银[1] LIN Yong-qing;LI Shi-ya;YANG Gui-ying;LIU Shi-meng;LIU Ran;LV Chang-yin(College of Public Health,University of South China,Key Laboratory of Hengyang for Health Hazard Factors Inspection and,Quarantine,Hengyang,Hunan 421001,China)

机构地区：[1]南华大学公共卫生学院衡阳市健康危害因子检验检疫新技术研究重点实验室,湖南衡阳421001

出　　处：《中国卫生检验杂志》2021年第3期257-261,共5页Chinese Journal of Health Laboratory Technology

基　　金：国家自然科学基金(81473021);湖南省大学生研究性学习和创新性实验计划项目(476)。

摘　　要：目的基于核酸适配体修饰的AuNPs与阳离子染料MG之间相互作用,以核酸适配体为识别元件,实现对Pb^(2+)高选择性的识别;选用AuNPs及MG作为探针元件,构建快速检测Pb^(2+)的新型核酸适配体生物比色传感器。方法以柠檬酸三钠为热稳定剂和还原剂制备AuNPs,将核酸适配体PW17吸附在纳米金颗粒表面。当体系中存在Pb^(2+)时,核酸适配体PW17能够被Pb^(2+)特异性地诱导变构形成G-四链体结构,游离的AuNPs在MG作用下发生聚集,反应体系颜色发生变化。结果在最优实验条件下,在0.25μmol/L-10μmol/L内,ΔA_(617/520)与Pb^(2+)浓度呈良好的线性关系,其线性回归方程为ΔA_(617/520)=0.072 C_(Pb)(×10^(-6)mol/L)-0.0267,r=0.997,该方法的检出限为0.17μmol/L。结论本研究富G序列的核酸适配体PW17能够与纳米金颗粒发生静电作用,拓展其发展成为一种新颖的核酸适配体传感器检测平台;该方法具有良好灵敏度,线性范围宽,应用前景良好可观。Objective This paper puts forward a method based on the interaction between AuNPs modified with nucleic acid aptamers and cationic dye MG.We constructed a novel colorimetric sensor for rapidly detecting Pb^(2+)by using nucleic acid aptamers as recognition elements to achieve high selectivity recognition of Pb^(2+)when AuNPs and MG are as colorimetric probes.Methods Gold nanoparticles(AuNPs)were prepared by trisodium citrate which is acted as deoxidizer and heat stabilizer and AuNPs are protected by adapters.When Pb^(2+)is present in the system,Pb^(2+)can specifically induce the aptamer PW17 to a G-quadruplex structure,and the free AuNPs aggregate under the action of the cationic dye malachite green(MG),causing the color change of the reaction system.Results Under the best experimental conditions,there was a linear correlation between Pb^(2+)andΔA_(617/520)in the range of 0.25 μmol/L-10μmol/L.The linear regression equation wasΔA_(617/520)=0.072 c_(Pb)(×10^(-6)mol/L)-0.0267,r=0.997.The detection limit is 0.17 μmol/L.Conclusion The nucleic acid aptamer PW17 of the G-rich sequence can electrostatically interact with the gold nanoparticles,so it is available to develop this method into a novel metal ion nucleic acid aptamer sensor detection platform.This method has strong sensitivity and excellent selectivity.The linear range is wide.The application prospect of this strategy in biosensors is promising.

关 键 词：铅 核酸适配体 纳米金 阳离子染料 分光光度法 

分 类 号：O657[理学—分析化学]