DNA模板的荧光双金属纳米簇在miRNA检测中的应用研究

Fluorescent noble metal nanoclusters have become one of the leading areas and hot topics on the nanomaterials science and analytical chemistry. Among them, the development of high-quality silver/gold bimetallic nanoclusters with the intense fluorescence and excellent stability would make up for the disadvantages of the monometallic ones, extend the practical applications of noble metal nanoclusters, and boost the development of fluorescent nanomaterials. Based on our recent works, we propose a facile, green approach to prepare DNA-templated fluorescent silver/gold bimetallic nanoclusters, as well as clarify the synthetic mechanism and regular pattern. Furthermore, we will design and construct the "turn-on" fluorescent sensing platforms for the selective and sensitive detection of the target miRNA. The platforms are based upon the reversibly competitive interaction of the DNA in the surface of fluorescent nanoclusters between the miRNA and two-dimensional nanomaterials, accompanied by fluorescence turn off-on process. Meanwhile, the construction and detection mechanism of the sensor platforms will be investigated through the physicochemical methods. This proposed project will not only follow closely the recent development of the relevant disciplines, but also blaze our own path for the synthesis and application of the fluorescent noble metal nanoclusters according to the mechanism. It may fill some technology gaps of the preparation and application of DNA-templated fluorescent nanoclusters, and provide the theoretical support for developing the novel method in the miRNA clinical detection.

贵金属纳米簇具有独特的荧光性质，是纳米材料科学和分析化学领域的前沿研究热点之一。其中，开发性能优异的荧光银金双金属纳米簇，能够弥补目前单金属纳米簇的不足，提升贵金属纳米簇的生物分析应用能力，促进荧光纳米材料领域的发展。本项目拟选择DNA作为模板，通过探索纳米簇的合成规律与生长机制，实现高质量银金双金属纳米簇的简单、绿色、可控合成；利用银金双金属纳米簇表面DNA与靶标miRNA及二维纳米材料之间相互作用引起的荧光变化，构建荧光增强型传感体系，实现对miRNA的选择性识别与灵敏检测；借助光谱学、热力学等实验手段，阐明传感体系的构建机理和识别机制，优化检测性能。本项目面向相关学科发展方向且独具特色，从机理出发进行新材料的合成与生物分析应用研究，既能丰富DNA保护纳米簇的合成方法和实际应用，又可以为拓展miRNA的临床检测方法提供理论支持。

贵金属纳米簇具有独特的荧光性质，是纳米材料科学和分析化学领域的前沿研究热点之一。其中，开发性能优异的荧光银金双金属纳米簇，能够提升贵金属纳米簇的生物分析应用能力，促进荧光纳米材料领域的发展，具有重要的研究意义和应用价值。在本项目中，我们探索了DNA作为模板的金属纳米簇合成规律与生长机制，发展了银纳米簇、银金双金属纳米簇简单、绿色、可控的合成方法，基于荧光金属纳米簇开发了一系列靶标miRNA的荧光增强型传感体系。具体包括：基于DNA保护荧光纳米簇的距离依赖性光诱导电子转移，设计构建了荧光增强型生物传感器检测miRNA-21；基于DNA保护荧光纳米簇与三链DNA分子信标，构建了荧光增强型生物传感体系检测miRNA-21及血管内皮生长因子等生物大分子；基于DNA特殊结构G-四链体/血红素的光诱导电子转移性质，构建了多功能荧光响应平台用于生物分析与简单逻辑运算；基于DNA杂交链反应引发的酶级联放大效应，建立了超灵敏光谱分析平台检测核酸及相关生物分子；基于DNA保护贵金属纳米簇等荧光物质的形成过程，利用传统酶联免疫分析策略构建了一系列荧光酶联免疫分析平台。本项目面向相关学科发展方向且独具特色，既能丰富荧光贵金属纳米簇的合成方法和实际应用，又可以为拓展miRNA等相关生物靶标分子的临床检测方法提供理论和技术支持。