Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering , Southwest University , Chongqing 400715 , P. R. China.
No. 1 High School of DaLian Development Area , Dalian , Liaoning 116000 , P. R. China.
ACS Appl Mater Interfaces. 2018 Apr 18;10(15):12491-12496. doi: 10.1021/acsami.8b01974. Epub 2018 Apr 6.
In this work, one stimuli-responsive DNA microcapsule was designed to combine duplex-specific nuclease (DSN) amplification strategy and surface-enhanced Raman spectroscopy (SERS) technology for sensitive detection of microRNA 155 (miRNA 155). First, toluidine blue (TB) as Raman dye and CaCO as core templates co-precipitated to form TB@CaCO composite. Then, DNA networks were layer by layer constructed with oligonucleotide layers cross-linked by linker ssDNA L to lock TB@CaCO inside. In the presence of ethylenediaminetetraacetic acid, the core CaCO would be dissolved to form TB-loading DNA microcapsule. With target miRNA 155-induced DSN signal amplification, a large amount of simulative target ssDNA D was obtained, which can completely complement with the linker L on the DNA networks, destroying the microcapsule to release TB and obtain a strong Raman signal. So by this smart design, a SERS platform was fabricated on the basis of the stimuli-responsive DNA microcapsule to detect miRNA 155 from 1 fM to 10 nM with a detection limit of 0.67 fM. In the present study, the programmable property and rapid response speed of DNA microcapsule, which helped in fabrication of a new potential biosensing technology for miRNA detection that is anticipated to be applied for clinical diagnosis.
在这项工作中，设计了一种响应性 DNA 微胶囊，将双链特异性核酸酶 (DSN) 扩增策略和表面增强拉曼光谱 (SERS) 技术结合起来，用于灵敏检测 microRNA 155 (miRNA 155)。首先，将甲苯胺蓝 (TB) 作为拉曼染料和 CaCO 作为核模板共同沉淀，形成 TB@CaCO 复合材料。然后，通过链接 ssDNA L 交联的寡核苷酸层逐层构建 DNA 网络，将 TB@CaCO 锁定在内部。在乙二胺四乙酸存在的情况下，核心 CaCO 将溶解形成 TB 负载 DNA 微胶囊。随着目标 miRNA 155 诱导的 DSN 信号放大，获得了大量模拟的目标 ssDNA D，它可以与 DNA 网络上的链接 L 完全互补，破坏微胶囊以释放 TB 并获得强拉曼信号。因此，通过这种智能设计，在响应性 DNA 微胶囊的基础上构建了 SERS 平台，用于从 1 fM 到 10 nM 的 miRNA 155 进行检测，检测限为 0.67 fM。在本研究中，DNA 微胶囊的可编程特性和快速响应速度有助于开发用于 miRNA 检测的新型潜在生物传感技术，有望应用于临床诊断。
