新型两亲性聚集诱导延迟荧光聚合物纳米粒子的制备及其光电性能研究

长寿命荧光材料的开发是生物荧光成像领域的研究热点。热激活延迟荧光（TADF）材料荧光效率高、寿命长，在时间分辨发光成像领域具有巨大的应用潜力。然而，TADF材料的三线态激子对氧气敏感，容易被氧淬灭，且大多数TADF分子生物相容性较差，极大地限制了其在时间分辨发光成像中的应用。针对以上问题，本项目提出通过化学共价键将聚集诱导延迟荧光与两亲性聚合物相结合，构建一系列具有良好生物相容性、对氧稳定的新型两亲性延迟荧光聚合物纳米粒子。通过聚合物自组装形成的纳米粒子对疏水性的延迟荧光基团进行包裹，进而隔绝氧气，增强材料的延迟荧光性能；其亲水性链段则延伸到水相中使其具有良好的水溶性，提高材料的生物相容性。通过设计多种两亲性延迟荧光聚合物，揭示聚合物化学结构和拓扑结构与自组装形貌及隔氧性能之间的关系。在此基础上，探索其在生物成像领域的应用，为拓展TADF材料在富氧体系中的应用提供实验依据和理论基础。

The development of long-lived fluorescent materials is a research hotspot in the field of bioluminescence imaging. Thermally activated delayed-fluorescence (TADF) luminophores characterize high efficiency and long fluorescence lifetime, showing great potential and advantages for time-resolved luminescence imaging (TRLI). However, the triplet states of TADF luminophores are highly sensitive and can be easily quenched in an oxygenic environment, and the biocompatibility of most molecules is poor, which greatly limits its application in TRLI. To address these problems, novel amphiphilic aggregation-induced delayed fluorescence polymer nanoparticles with good biocompatibility and oxygen-insensitive will be fabricated by combining aggregation-induced delayed fluorescence with the amphiphilic polymer through chemical covalent bond in this research. The hydrophobic delayed fluorescence groups are encapsulated by these self-assembled nanomicelles, which can isolate the oxygen and enhance the delayed fluorescence properties. Meanwhile, the hydrophilic chain segments extend to the water phase to make them have excellent water solubility and improve the biocompatibility of the material. The relationship between the chemical structure and topological structure of amphiphilic delay fluorescent polymers and the self-assembly morphology and oxygen barrier properties will be revealed. On this basis, the application in the field of biological imaging will be further explored, which will provide experimental and theoretical basis for expanding the application of TADF materials in oxygen-rich system.