荧光铜纳米粒的发卡型DNA模板设计和应用

Compared with other fluorescent metal nanoparticles (gold, silver and platinum NPs), DNA-templated fluorescent copper nanoparticles (CuNPs) are a type of newly emerged fluorescent probe and has attracted considerable interest, by virtue of low cost, rapid and simple preparation. Currently, research of DNA templated CuNPs focus on double-strand DNA and linear poly T. Recently, our research group found that the hairpin DNA with poly-T loop cound be the excellent template for the formation of fluorescent CuNPs. Compared with linear poly T and double-strand DNA, the fluorescent intensity ratio (signal/noise) obtained an overlay and enhancement effects. Herein, based on that, we aim to develop a series of new hairpin DNA templates with different loops, stems and length, and try to make it clear that the relationship lies in the template and the formation of fluorescent CuNPs, and then study the formation mechanism and seek the way to improve its stability. After that, we make efforts to establish the simple, rapid and sensitive protocols for different targets, such as small biomolecules, nucleic acid, enzyme and its inhibits. As a result, this project will enrich the pool of DNA templates for CuNPs with outstanding photophysical properties, in further elucidate the formation mechanism, and then supervise the design of DNA templated-CuNPs-based fluorescent techniques. All of these will greatly promote the development of CuNPs in the research field of analytical chemistry.

相比于金、银和铂纳米簇，荧光铜纳米粒具有成本低、制备迅速、条件温和等特点，已成为荧光纳米材料领域的研究热点之一。目前荧光铜纳米粒制备采用的DNA模板集中在双链模板和线性多聚脱氧胸苷（poly T）模板。我们最近研究发现：采用环部为poly T的发卡型DNA模板合成荧光铜纳米粒，荧光信号大幅增强，呈现出poly T和双链模板的叠加和增敏效应。本项目拟在此基础上，设计和发展发卡型DNA新模板，并探讨铜纳米粒的荧光性能与模板序列的内在相关性，探究其形成机理，提高其稳定性，从而获得性能优良的荧光铜纳米材料。随后，构建多种免标记、均相快速的荧光分析新技术，应用于生物小分子、核酸、酶及其抑制剂等目标分子检测。该项目的成功实施将进一步丰富荧光铜纳米粒的DNA模板类型，提高其荧光性能和阐释纳米粒形成机理，拓宽其应用范围，大力促进荧光铜纳米粒在分析领域的发展。

本课题以环部为多聚脱氧胸腺嘧啶核苷酸（poly-T）的发卡型DNA 作为模板，用以制备荧光铜纳米粒。相比于相同长度的poly T和相同的双链序列而言，荧光性能显著升高。课题中详细探讨了模板的茎部、环部序列类型以及长度，以及其它试剂对于所形成的荧光铜纳米粒的影响。在此基础上，基于新模板形成荧光铜纳米粒为检测信号，构建了烟酰胺腺嘌呤二核苷酸（NAD+）、氨基酸、核酸酶、miRNA和转录因子简便快速的生物传感技术。随后，利用核苷酸与酶的特异性作用，与介孔二氧化硅纳米材料结合，构建了基于目标物刺激响应的化学发光检测技术，用于疾病相关酶和食品中细菌污染监测技术，以及一种具有抗菌功能的多孔光热膜用于水蒸发处理。不仅拓展了荧光铜纳米粒的应用范围，且开发了新的研究领域。围绕本课题，发表论文3篇，《Talanta》，《Analytical and Bioanalytical Chemistry》和《Journal of Materials Chemistry A》各1篇。另有2篇文章正在审稿中，申请专利1项。