基于聚集诱导发光特性的共轭微孔聚合物纳米粒子的制备及传感应用

Conjugated microporous polymers (CMPs) have great potential in the field of fluorescence sensing, due to their good luminescence and inherent porosity. The CMPs synthesized from conventional polymerization methods are normally insoluble powders, which are difficult to process and even more difficult to realize aqueous phase detection. Although, the realization of high performance nitroaromatic explosive and metal ion fluorescence detection in aqueous phase is a conundrum in sensing field. In order to improve the sensing sensitivity and selectivity, the preparation of novel particle-size adjustable and stable water dispersible CMP nanoparticles with high fluorescence quantum yields is proposed, combining the porosity of the CMPs and aggregation induced emission effect, and their fluorescence sensing properties will be investigated. By introducing a series of identification units with different chemical and electronic structures, CMP nanoparticle sensing material system is constructed to detect the trace nitroaromatic explosives and metal ions with high efficiency in aqueous phase; with the preparation of near-infrared CMP nanoparticles, their application in fluorescence bioimaging will be explored. In this proposal, the preparation of CMP nanoparticles and their fluorescence sensing properties will be systematically researched and the relationship between sensing properties and microenvironment of the sensitive groups will be explored, to establish the method to improve the sensitivity and selectivity in aqueous fluorescence sensing. Eventually, the project is aimed to develop highly-sensitive, highly-selective and fast-responsive CMP nanoparticle material system for sensing analysts.

共轭微孔聚合物（CMPs）由于其优良的发光性能及固有的孔特性在荧光传感领域具有巨大应用前景。传统方法制备的CMPs通常为不溶粉末，难以加工，更不易实现水相检测。而实现高效水相硝基爆炸物及金属离子荧光检测是传感领域中的一个难题。本项目从提高传感体系灵敏度和选择性出发，提出将CMPs的孔道特性与聚集诱导发光特性相结合，通过Suzuki细乳液聚合方法制备新型粒径可调、可稳定水相分散的高发光效率CMP纳米粒子并探索其荧光传感应用。通过引入不同化学及电子结构的识别单元构筑聚合物传感材料体系，实现对痕量硝基爆炸物及金属离子的高效水相荧光检测；制备近红外CMP纳米粒子，探索其在生物荧光成像领域的应用。本项目将系统研究CMP纳米粒子的制备方法及其荧光传感性能，探索敏感基团微环境与传感特性之间的关系，建立提高水相荧光传感灵敏度和选择性的方法，发展对分析质具有高灵敏、高选择、快响应的CMP纳米粒子材料体系。

硝基芳香爆炸物，包括TNT（2,4,6-三硝基甲苯）、PA（苦味酸，即2,4,6-三硝基苯酚）、DNT（2,4-二硝基甲苯）等，具有高爆炸性和高毒性，对社会稳定和人身安全造成严重威胁，且易造成土壤、水资源的污染。因而，对硝基爆炸物的高灵敏气相及水相检测具有重要意义。在各种硝基爆炸物的检测方法中，荧光传感具有高灵敏度和高选择性特征，且易于实现现场实时检测。传感材料是荧光传感的核心，本项目从提高传感体系在水相中的灵敏度和选择性出发，将共轭微孔聚合物的孔道特性与聚集诱导发光特性相结合，发展高发光效率聚合物纳米粒子用于硝基爆炸物的气相和水相检测。具体包括：1.通过Suzuki细乳液聚合方法，采用含有富电子基团三苯胺、聚集诱导发光基团四苯乙烯等，制备了一系列粒径均匀且在水相中稳定分散的高发光效率共轭多孔聚合物纳米粒子；2.系统研究了各类共轭多孔聚合物纳米粒子对硝基爆炸物的荧光传感特性，获得了对PA具有高灵敏度、高选择性及抗干扰性的传感体系，检测限低至几十ppb；3.系统研究了聚合物纳米粒子对不同硝基爆炸物的荧光传感机理，建立了提高硝基爆炸物荧光传感灵敏度和选择性的设计指针；4.利用制备的聚合物纳米粒子对含有PA的实际环境水样进行了检测，结果表明在95%置信度内本项目的聚合物荧光传感技术和采用HPLC分析结果一致，证明该检测结果具有高度的可靠性。本项目的实施为实现水相中硝基爆炸物，特别是针对PA的高灵敏、高选择性检测提供了科学依据和技术支撑，实现了预期研究目标和技术指标。项目执行期间，基于相关研究成果整理、发表了一系列SCI学术论文。