构建功能化金属纳米簇-碳量子点复合材料荧光探针应用于细胞内活性氧检测

Reactive oxygen species have been demonstrated to be directly related to pathophysiological processes, and the inherent characteristics limit their sensitive detection. Metal nanoclusters and carbon quantum dots have attracted growing attention in the field of fluorescent nanomaterials in the past decade and have been widely applied in cell imaging, sensing and drug delivery because of their tunable optical properties and excellent biocompatibility. In this project, we are going to exploit metal nanoclusters-carbon quantum dots hybrid material with high fluorescence resonance energy transfer efficiency based on chemical crosslinking approach and investigate the relationship between their fluorescence characters and structures. We also aim to develop sensitive intracellular reactive oxygen species (hydrogen peroxide was selected in this project) fluorescence probe via the combination of fluorescence resonance energy transfer between the metal nanoclustersand carbon quantum dots and the intrinsic peroxidase-like activity of carbon quantum dots, which catalyzes the decomposition of hydrogen peroxide and the generation of hydroxyl radicals. In addition to extend the research of metal nanoclusters and carbon quantum dots, this project also deepens the understanding of their properties at micro-scale level, which is of great importance to the fundamental studies and analytical applications of metal nanoclusters, carbon quantum dots and reactive oxygen species.

活性氧化合物在体内浓度的变化与生理、病理直接相关，且其固有特性使高灵敏检测存在巨大挑战。金属纳米簇和碳量子点是近十年间在荧光纳米材料领域新兴的热点，它们具有光学性质可调和生物相容性良好等特性，被广泛应用于细胞成像、检测或药物输送。本项目拟以化学交联法制备高效荧光共振能量转移金属纳米簇-碳量子点复合材料，并研究复合材料结构与荧光性能的内在联系。结合金属纳米簇-碳量子点之间荧光共振能量转移和碳量子点催化过氧化氢分解产生羟自由基的特性，构建高灵敏细胞内活性氧（本项目以过氧化氢为对象）荧光探针。本项目的成功实施，将拓展金属纳米簇与碳量子点研究领域，加深研究者在微观尺度对金属纳米簇和碳量子点纳米材料的性质认知，对金属纳米簇和碳量子点纳米材料及活性氧响应的基础与应用研究具有重要意义。

本研究以提高复合材料发光性能为目标，研究金属纳米簇-碳量子点纳米复合材料的发光性能，设计金属纳米簇-碳量子点复合纳米材料荧光探针。项目从金纳米簇和碳量子点制备，模板或者前驱体对金、银纳米簇及碳量子点发光性能的影响和机理，表面官能团对复合纳米材料性能影响等方面展开，取得如下成果：（a）将碳量子点与金属纳米簇结合起来，构建了高性能纳米复合荧光材料，实现了多级结构纳米材料功能导向性设计；（b）认识无机荧光纳米材料结构和组成对复合材性能的影响机理和规律，对构筑基于金属纳米簇和碳量子点的高性能发光材料的基础理论研究具有重要意义；（c）提高荧光共振能量转移效率，设计通用型荧光探针。