Ag^+稳定的剪刀形三螺旋分子开关快速灵敏检测转录因子  

Ag^+-stabilized forficiform triple helix molecular switch for rapid and sensitive detection of transcription factor

作　　者：朱德颂 褚秀玲 艾仕云[1] ZHU De-song;CHU Xiu-ling;AI Shi-yun(School of Chemistry and Materials Science,Shandong Agricultural University, Tai'an 271018;Tai'an City Environmental Protection Testing Station, Tai'an 271000)

机构地区：[1]山东农业大学化学与材料科学学院,泰安271018 [2]泰安市环境保护检测站,泰安271000

出　　处：《分析试验室》2019年第7期787-791,共5页Chinese Journal of Analysis Laboratory

基　　金：中国博士后科学基金面上项目(2018M632697)资助

摘　　要：构建了基于银离子稳定的剪刀形三螺旋分子开关的荧光传感器,中性环境下快速灵敏检测转录因子。银离子促使剪刀分子信标的两条臂(标记荧光基团的双链臂和标记猝灭基团的单链臂)相互靠近,剪刀闭合,形成剪刀形三螺旋开关。转录因子不存在时,剪刀处于闭合,三螺旋开关"关闭",荧光基团和猝灭基团发生荧光共振能量转移,荧光被猝灭。转录因子存在时,特异性结合包含在开关双链臂中的双链识别序列,取代单链臂,剪刀张开,三螺旋开关"打开",猝灭基团远离荧光基团,荧光恢复。最佳条件下,转录因子浓度在0. 5~50 nmol/L范围内,荧光强度与其浓度呈线性关系,检测限0. 3 nmol/L。A rapid and sensitive fluorescence sensor for the detection of transcription factor in neutral environment based on Ag+-stabilized forficiform triple helix molecular switch(Ag+-FTHMS) was presented. Ag+urged two arms of the forficiform molecular beacon(the double-stranded arm labeled with the fluorophore and the single-stranded arm labeled with the quenching group) to be close to each other to form Ag+-FTHMS. In the absence of transcription factor,the scissors were closed(Ag+-FTHMS was "off "),which led to fluorescence resonance energy transfer(FTET) between the fluorescence group and quenching group. As a result,fluorescence was quenched. In the presence of transcription factor,it specifically bound to the double-stranded recognition sequences in the Ag^+-FTHMS and replaced the single-stranded arm,which opened the scissors and destroyed the structure of switch(Ag^+-FTHMS was "on"). As a result,the quenching group was far from the fluorophore and the fluorescence was restored. Under the optimal conditions,the fluorescence intensity was linear with the concentration of transcription factor in the range of 0. 5 ~ 50 nmol/L and the limit of detection was 0. 3 nmol/L. This sensor showed good selectivity and potential applicability in the detection of actual samples.

关 键 词：银离子 剪刀形三螺旋分子开关 转录因子 快速 灵敏 检测 

分 类 号：O652[理学—分析化学]