基于表面等离子体共振成像的量子隧穿效应及单microRNA分子检测

MicroRNA is a non-coding single-strand endogenous RNA with a length of 21-25 base pairs, which is involved in the regulation of post-transcriptional gene expression in organisms. These small RNA molecules are closely related to the evolution of their target genes. As these microRNA show low expression levels and small molecular size, a highly sensitive analytical technique is required to study individual microRNA..This project aims to use surface plasmon resonance imaging microscope to perform highly sensitive, label-free dynamic imaging detection of individual microRNA. Gold nanoparticles modified single-strand DNA (ssDNA) are hybridized with single microRNA to form double strand conjugated structure, and then the distance between single nanoparticle and gold substrate is changed by the cleavage of double strand enzyme. Different surface plasmon resonance imaging analysis before (no electron tunneling) and after cleavage (electron tunneling) can obtain information of single microRNA molecule.

MicroRNA是一种长度为21-25个碱基对的非编码单链内源性RNA，在生物体中参与转录后基因的表达调控。这些小分子RNA与其靶基因的进化有着密切的关系。由于这些microRNA表达水平低且分子较小，因而需要高灵敏度的分析方法对单个microRNA进行研究。. 本项目旨在运用表面等离子共振成像显微镜对单个microRNA进行高灵敏，免标记动态成像检测。运用金片表面修饰有单链DNA（ssDNA）的金纳米粒子与单个microRNA的结合形成双链共轭结构，再通过双链酶的剪切作用得到单纳米粒子与金片基底的距离改变。剪切前（无电子隧穿）与剪切后（电子隧穿）的不同表面等离子体成像分析得到单个microRNA的信息。

本项目运用表面等离激元共振成像技术对单纳米颗粒与基底之间的电子隧穿过程及耦合效应的动态转换过程进行高灵敏成像研究，同时开展了一系列基于上述技术方法的生物分子成像分析。运用金片表面修饰有单链DNA（ssDNA）的金纳米粒子与单个microRNA的结合形成双链共轭结构，再通过双链酶的剪切作用得到单纳米粒子与金片基底的距离改变。剪切前（无电子隧穿）与剪切后（电子隧穿）的不同表面等离激元成像分析得到单个microRNA的信息。相关成果发表在Proceedings of the National Academy of Sciences of the United States of America、Analytical Chemistry、Chemical Science和JACS Au等期刊上。