基于DNA四面体的响应型比率光声探针用于活体内microRNA检测研究

MicroRNA对生物体中一系列生命过程起着重要的调控作用，对其进行实时活体分析对于其生物功能研究及肿瘤的诊断至关重要。本项目创新性地将响应型比率光声检测体系和DNA四面体载体相结合，设计及构建新型纳米光声探针，用于活体内实时监测肿瘤部位microRNA的表达分析。一方面，该项目创新性地结合红外染料距离变化及接触式淬灭产生比率光声信号，构建了针对microRNA特异响应的比率光声探针，实现对目标分子的定量分析。另外一方面，借助DNA纳米自组装技术，构建了新型优异的光声探针载体：DNA四面体。该载体在生物相容性、结构均一稳定性、细胞摄取及表面功能等方面，具有突出表现，有力地协助并实现了特异响应的比率光声探针在活体内的microRNA表达分析。本项目将为microRNA生物分析及生物功能研究提供新方法与新技术，同时对肿瘤microRNA的活体实时监测及定量分析具有重要意义。

MicroRNA plays an important role in the control of a series of life processes in the organism. Real-time living analysis of microRNA is very important for its biological function research and diagnosis of tumor. This project creatively combines the activatable ratiometric photoacoustic detection system with the DNA tetrahedron carrier to design and construct a new nano-photoacoustic probe for real-time monitoring of the expression of microRNA in the tumor site. On the one hand, this project creatively combines the variation of the infrared dye distance and the contact quenching to produce ratiometric photoacoustic signal, and constructs a ratiometric photoacoustic probe for the specific microRNA with quantitative analysis. On the other hand, based DNA nano self-assembly technology, a new type of excellent photoacoustic probe carrier, DNA tetrahedron, is constructed. The carrier plays outstanding performance in biocompatibility, structure uniformity stability, cell uptake and surface function. These advantages of carrier will play important roles in effectively assisting and realizing the specific microRNA expression analysis with ratiometric photoacoustic probe in vivo. This project will provide new methods and new techniques for microRNA biological analysis and its biological function research, and have great significance for real-time monitoring and quantitative analysis of tumor microRNA in vivo.