基于分子间裂分G-四链体-氯化血红素DNA酶自组装纳米线的“Turn-on”型汞离子传感研究  

“Turn-on” Sensor for Detection of Mercury Ion through Autonomous Assembly of Intermolecular Splitting G-Quardruplex-Hemin DNAzyme Nanowires

作　　者：张何[1] 赵智粮 傅昕[1] 王青 ZHANG He;ZHAO Zhiliang;FU Xin;WANG Qing(School of Chemistry and Chemical Engineering,Hunan Institute of Engineering,Xiangtan Hu’nan 411104,China)

机构地区：[1]湖南工程学院化学化工学院,湖南湘潭411104

出　　处：《传感技术学报》2018年第12期1822-1827,共6页Chinese Journal of Sensors and Actuators

基　　金：国家自然科学基金项目(21005067);湖南省教育厅资助科研项目(17A044;16B060)

摘　　要：以聚苯乙烯微球为载体,利用杂交链式反应,发展了一种基于T-Hg^(2+)-T特异性识别及串联分子间裂分G-四链体-血红素DNA酶纳米线催化信号放大的Hg^(2+)"Turn on"型高灵敏生物传感器。当汞离子存在时,"T-Hg^(2+)-T"特殊结构的形成促使微球表面修饰的富T探针打开并捕获设计的发夹探针P1,由此引发与发夹探针P2之间的杂交链式反应。由于P1、P2的5'游离末端及3'游离末端都包含富G序列,通过杂交链式反应相互拉近并串联排列,在微球表面折叠形成包含串联分子间裂分G-四链体-血红素DNA酶的自组装DNA纳米线。在最优实验条件下,传感器对Hg^(2+)的线性检测范围为2 pmol/L～1 nmol/L,检出限为1.5 pmol/L;当试样中的共存离子大量存在时,传感器对Hg^(2+)仍然具有高的选择性。此方法检测Hg^(2+)具有良好的选择性、灵敏度及稳定性。Based on T-Hg^2+-T structure for specific recognition and the tandem intermolecular splitting G-quadruplex-hemin DNAzymes nanowires for catalytic signal amplification,a highly sensitive“Turn-on”biosensor for detection of Hg^2+was developed on the polystyrene microbeads using the hybridization chain reaction.When Hg^2+was present in reaction system,the formation of T-Hg^2+-T special structure prompted T-rich DNA probes modified on the microbeads to open and capture the designed hairpin probe P1,which triggered the hybridization chain reaction between hairpin probe P1and hairpin probe P2.Since the5′free terminal and the3′free terminal of hairpin probe P1and P2both contain the G-rich sequences which are contacted closely with each other and arranged in series through hybridization chain reaction,and the neighbouring G-rich sequences further fold to form autonomously assembled nanowires containing tandem intermolecular splitting G-quardruplex-hemin DNAzyme on the interface of polystyrene microspheres.Under the optimal experimental conditions,the linear range for detection of Hg^2+was2pmol/L^1nmol/L,and the detection limit was1.5pmol/L.The sensor still has a high selectivity to Hg^2+when the coexisting ions in the sample are abundant.The sensor had good selectivity,sensitivity,and stability for Hg^2+analysis.

关 键 词：汞离子检测 生物传感器 比色分析 分子间裂分G-四链体 DNA纳米线 DNA酶 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]