氧化石墨烯/半导体量子点间FRET的高分子介导调控及其传感应用

The sensor of fluorescence resonance energy transfer (FRET) between graphene oxide(GO) and quantum dots (QDs) has attracted more and more attention for its excellent properties. Many studies was in liquid system still bear some drawbacks such as GO is easy to aggregate, it is difficult to accurately control the distance between GO and QDs etc. The project is proposed to construct a polymer composite film will load GO and QDs. With the help of the electrostatic interaction and chemical reaction, graphene oxide will uniformly disperse and immobilize in the CS film matrix. QDs will be introduced into the composite film by in-situ synthesis, the sensing elements will be concentrated in the film and it’s quantity will be improved. A series of different structure films will be obtained by adjusting the preparation conditions. The detection such as polyelectrolyte(DNA, protein), acidic gas and base gas will induce the changes of the chitosan conformation, the sensing element will response on the spatial of the film to achieve the precise control of the distance between the graphene oxide and quantum dots, which will enhance or weaken the FRET effect, realize to detect the target molecules. The relevancy between the structure of the composite film and FRET will be obtained, the micromechanism of the fluorescence sensing behavior will be revealed. Combining the theory and experiment, the new method to the multiple factors of FRET composite film will be constructed, the study will promote to establish the theoretical foundation for the novel optical sensing platform.

氧化石墨烯(GO)与量子点间(QDs)的荧光共振能量转移(FRET)传感器因其优异的性能而备受关注。但众多处于均相的研究体系存在GO易于聚集、难以精准调控GO与QDs之间距离等问题。基于此，本项目拟开展高分子壳聚糖(CS)薄膜负载GO与QDs新型传感器构建研究。借助静电作用和化学反应实现GO在CS薄膜中的均匀分散与固定化，以原位合成等方法向薄膜引入QDs，调控制备条件，提高传感元素引入量，获得系列结构复合薄膜。以能够诱发CS构象变化的聚电解质(DNA、蛋白质)、酸性气体、碱性气体等为检测对象，刺激高分子构象变化，从而引起GO与QDs在薄膜中相对距离的变化，增强或弱化FRET效应，实现对目标分子的传感。通过深入研究复合薄膜特征结构与FRET的内在关系,揭示荧光传感的微观机制，以期从理论与实验结合上，建立多因素参与的FRET传感复合薄膜构建新方法，为发展新型光学传感器奠定基础。

目前，随着交叉学科的迅猛发展，荧光传感材料以其快速检测、稳定性好、灵敏度高、使用方便及成本低等特点备受关注，因而在生物分析检测和医药领域受到了人们极大的重视。本项目通过外源物对壳聚糖分子链构象的改变调控供体与受体的相对空间距离，实现新型 FRET 荧光传感器的构建。利用高分子链介导的量子点间 FRET 新型光学传感器，实现了对环境污染物的微量检测。通过对传感器 FRET 荧光传感行为的探索性研究，在化学传感器综合性能上有了新的突破，丰富和拓展了新型薄膜材料的设计思路，为构建环境友好、高灵敏度和高选择性光学传感材料的研发提供理论依据。通过本课题的资助，共发表 SCI 研究论 14 篇，申请专利 5 项，其中授权发明专利 2 项，线下参加了 2 次学术会议。线上参加 8 次学术会议。