新型有机荧光纳米温度计的构建及其在活细胞温度检测中的应用

温度是细胞活动最重要和最基本的参数之一，生物体的各种代谢活动和疾病状态均伴随着温度变化，因此细胞内温度检测具有十分重要的意义。然而，传统的有机荧光纳米温度计在检测准确度和灵敏度上存在一定的局限性。为了解决有机荧光纳米温度计中存在的问题，本项目拟利用天然来源饱和脂肪酸为热响应性材料、聚集诱导发光（AIE）材料为环境响应性荧光团构建温度响应型纳米粒子，结合原位封装聚合技术制备具有核壳结构的有机荧光纳米温度计，利用多种检测参数实现活细胞内温度的高准确度和高灵敏检测。其中，具有AIE性质的环境响应性荧光团用于提高有机探针的光稳定性，熔程窄且相变快的饱和脂肪酸用于放大环境响应性荧光团的信号变化，原位封装聚合技术用于提高荧光纳米温度计在复杂细胞环境中的抗干扰能力。通过本项目的实施，我们希望建立活细胞温度检测的全新平台，研究细胞在不同生理状态下的热变化行为，从而在微观层面上辅助理解和揭示更多的生命过程。

Temperature is one of the most important and fundamental parameters for cell activities, and its variation is highly associated with various metabolic activities and pathological states of organisms. It is thus of great importance to achieve intracellular temperature measurement. However, for traditional organic fluorescent nanothermometers, there remain limitations in terms of the detection accuracy and sensitivity. To address the issues encountered in organic fluorescent nanothermometers, thermo-responsive nanoparticles are first prepared by using naturally-occurring saturated fatty acids as the thermo-responsive matrix and aggregation-induced emission (AIE) materials as the environmentally responsive fluorophores. The organic fluorescent nanothermometer with a core-shell structure is further constructed via in situ polymerization on the surface of the thermo-responsive nanoparticles. Taking advantage of a set of detection parameters, we are able to achieve the accurate and sensitive temperature measurement in living cells. Notably, we herein employ the environmentally responsive fluorophores with AIE properties to improve the photostability of organic probes, saturated fatty acids with narrow melting range and fast phase transition to amplify the signal variation of the environmentally responsive fluorophores, and in situ polymerization technology to prevent interference from the complex intracellular environment toward the fluorescent nanothermometer. Through the implementation of this project, we anticipate to establish a new platform for temperature measurement in living cells, which can be used to study how cells react to heat variation in different physiological conditions and is helpful to understand and unveil more life processes from a microscopic perspective.