基于双发射免标记核酸探针的比率型荧光传感器用于银的检测  

A silver ionratiometric fluorescence sensor by using label-free dual emission DNA probe

作　　者：李亚楠 王俊平[1] LI Yanan;WANG Junping(State Key Laboratory for Food Nutrition and Safety,College of Food Engineering and Biotechnology,Tianjin University of Science and Technology,Tianjin 300457)

机构地区：[1]食品营养与安全国家重点实验室天津科技大学食品工程与生物技术学院

出　　处：《分析试验室》2020年第1期12-16,共5页Chinese Journal of Analysis Laboratory

基　　金：国家重点研发项目(2016YFD0401202);天津创新平台专项(17PTGCCX00230)资助

摘　　要：构建了一种新型免标记的双发射荧光比率核酸探针(GelRed/[G40]/Tb^3+)并用于Ag+的检测。对于GelRed/[G40]/Tb^3+探针,GelRed作为一种核酸染料嵌入到单链DNA-[G40]中,形成的GelRed/[G40]作为稳定的内置参照标准,在激发波长290 nm处,发射荧光强度固定不变的红色荧光(发射波长为635 nm),而[G40]/Tb^3+作为敏感的响应信号,随着Ag^+浓度的增加,产生的绿色荧光逐渐增强(发射波长为545 nm),[G40]/Tb3+与GelRed/[G40]发射的荧光强度比值也发生相应的改变,从而实现对Ag^+的定量检测。在优化的实验条件下,[G40]/Tb^3+与GelRed/[G40]荧光强度比值和Ag^+浓度在0~7.5μmol/L的范围内具有较好的线性关系,Ag^+检出限为0.156μmol/L。本传感器在10 min内就可完成对Ag^+的分析。方法已用于自来水样中Ag^+的检测,与ICP-MS法检测结果一致。A novel method based on label-free dual-emission ratiometric fluorescent probe(GelRed/[G40]/Tb^3+)for Ag+detection was presented.For GelRed/[G40]/Tb3+probe,the excitation wavelength was set at290 nm,GelRed/[G40](GelRed as nucleic acid dye intercalated into the single-stranded DNA[G40])acted as a stable build-in reference standard with red emission(emission wavelength at 635 nm),[G40]/Tb^3+acted as sensitive response signal with green emission(emission wavelength at 545 nm).The fluorescence intensity ratio of[G40]/Tb^3+and GelRed/[G40]can be used to precisely detect the concentration of Ag^+,because Ag+can increased significantly the green fluorescence of[G40]/Tb^3+,where as the inner red fluorescence of GelRed/[G40]remained unchangeable.Under the optimum experimental conditions,the ratio of fluorescence intensity increased gradually with Ag^+concentration increasing in the range of 0-7.5μmol/L,exhibiting good linearity.The detection limit of Ag^+was 0.156μmol/L.The detection of Ag^+can be accomplished within 10 min using this ratiometric fluorescence sensor.This detection platform was applied for determination of Ag^+in tap water samples,and the results of this method were in good agreement with that obtained from the inductively couded plasma mass spectrometry.

关 键 词：GelRed TB3+ DNA 免标记 比率型荧光传感器 AG^+ 

分 类 号：O657.39[理学—分析化学]