摘要
构建了一种基于toehold链置换反应(TSDR)驱动的三足DNA步行器比率荧光传感方法,用于土霉素(OTC)的灵敏检测。当OTC存在时,其适配体可特异性识别OTC并释放引发链AP, AP在TSDR反应驱动下引导发夹链组装(CHA),形成三足DNA步行器。三足DNA步行器在TSDR反应驱动下继续引发CHA反应,实现荧光共振能量转移(FRET),以此实现信号扩增,完成对目标物的灵敏检测。在最佳检测条件下,该传感器在OTC浓度0.1 pmol/L~10 nmol/L范围内与FRET信号强度成线性关系,检出限(LOD)低至0.08 pmol/L。检测牛奶样品时的回收率为98.7%~101.7%,相对标准偏差为1.7%~3.0%,该方法在实际样品分析中具有良好的应用前景。
A three-legged DNA walker ratio fluorescence sensing method based on toehold strand displacement reaction(TSDR)was developed for the ultrasensitive detection of oxytetracycline(OTC).When OTC exists in system,the adapter is capable of specifical recognizing it and releasing the trigger chain AP,which guides hairpin chain assembly(CHA)driven by TSDR reaction,and forming a three-legged DNA walker.The three-legged DNA walker continues to trigger CHA reaction driven by TSDR reaction,achieving fluorescence resonance energy transfer(FRET)to amplify the signal,furtehr achieve sensitive detection of the target substance.Under the optimal detection conditions,the sensor exhibits a linear relationship between FRET signal intensity and the OTC concentration range of 0.1 pmol/L-10 nmol/L,with a detection limit(LOD)as low as 0.08 pmol/L.The recovery rate of detecting milk samples was 98.7%-101.7%,and the relative standard deviation was 1.7%-3.0%.This method possesses application prospects in actual sample analysis.
作者
王丽娜
罗志
张立
WANG Lina;LUO Zhi;ZHANG Li(Guangdong Polytechnic of Environmental Protection Engineering,Foshan 528216,China;College of Environmental and Chemical Engineering,Nanchang Hangkong University,Nanchang 330203,China)
出处
《分析试验室》
2025年第12期1808-1816,共9页
Chinese Journal of Analysis Laboratory
基金
广东省2024年度教育科学规划课题(高等教育专项)(2024GXJK1137)
广东环境保护工程职业学院自然科学类(人才引进-博士)项目(K640123062506)资助。
关键词
链置换(TSDR)反应
催化发夹组装
三足DNA步行器
比率荧光传感器
toehold-mediated strand displacement reaction(TSDR)
catalytic hairpin assembly
three-legged DNA walker
ratio fluorescence sensor
