光镊捕获单个上转换发光微纳复合物颗粒对链置换反应引发解组装过程的实时探测  

Real-Time Detection of Disassembling Process Induced by Strand Displacement Reaction Based on Optical Trapping of Single Upconversion Luminescence Micro-Nano Composite Particles

作　　者：宋重阳 康亚峰 李诚予 庞代文[1] 唐宏武[1] SONG Chong-yang;KANG Ya-feng;LI Cheng-yu;PANG Dai-wen;TANG Hong-wu(Key Laboratory of Analytical Chemistry for Biology and Medicine(Ministry of Education),College of Chemistry and Molecular Sciences,Wuhan University,Wuhan 430072)

机构地区：[1]生物医学分析化学教育部重点实验室武汉大学化学与分子科学学院

出　　处：《分析科学学报》2019年第4期397-403,共7页Journal of Analytical Science

基　　金：国家自然科学基金(No.81572086,81772256,21827808)

摘　　要：借助980 nm激光光镊实时观测了链置换反应引发的单颗微纳复合物(Micro-Nano Composites,MNCs)颗粒的解组装过程。MNCs由核心NaYF 4微米颗粒(Micro-Particles,MPs)和卫星式组装的上转换纳米颗粒(Upconversion Nanoparticles,UCNPs)组成,在进攻链(Invader strand)引发链置换反应后发生解组装。借助980 nm激光光镊辅助的显微成像平台,可实现单颗MNCs的同时捕获和激发。UCNPs具有出色的光稳定性,因此可以长时间测定无光漂白的发光信号。发光信号变化反映链置换引发的单颗MNCs的解组装,信号变化速度与Invader strand的浓度相关。浓度低至1 nmol/L的Invader strand即可在数分钟内产生可观测的信号变化。因此,MNCs可以用作一种DNA微传感器,有望应用于复杂生物体系中DNA/RNA的实时检测。Disassembling process of single micro-nano composites(MNCs)particles induced by strand displacement reaction was real-time observed,with the assistance of 980 nm optical tweezers.MNCs,which is composed of a core NaYF 4 micro-particles(MPs)and satellite upconversion nanoparticles(UCNPs),disassembled when invader strand initiated strand displacement reaction.Using a 980 nm optical tweezers-assisted imaging plateform,single MNCs could be trapped and simultaneously excited.Benefiting from the excellent photostability of UCNPs,long-time continuous measurement of non-bleaching luminescence was realized.The variation of the luminescence intensity,arising from disassembling of single MNCs induced by strand displacement reaction,is dependent on the concentration of the invader strand.The data show that the presence of 1 nmol/L invader strand induced a measurable signal variation within several minutes.Therefore,MNCs could be used as micro-sensors for DNA detection,and might be further applied for real-time detection of DNA/RNA in complex bio-systems.

关 键 词：光镊 上转换发光 链置换 单颗粒 实时探测 

分 类 号：O657[理学—分析化学]