树枝状咔唑类共轭聚合物荧光探针的合成与研究

Mercury(Ⅱ) ion is a kind of high dangerous ion because of their inherent toxic effect on human health and ecological environment. The traditional detection methods were neutron activation analysis, anodic stripping voltammetry, inductively coupled plasma mass spectrometer, and so on. However, most of these methods require expensive instruments, professional personnel and skilled operation. Among these reported methods, optical probes, especially conjugated polymers (CPs)-based optical probes displayed interesting advantages, such as high sensitivity, excellent selectivity and real-time usability. In the early time , straight-chain carbazole-based conjugated polymers have been studied and can be used as a kind of optical probe material to detect Hg2+. However，these dendritic carbazole-based conjugated polymers used as mercury ion-optical probes have not been reported. In order to further improve the selectivity, sensitivity, interference resistance of mercury ion-optical probe, this study was performed in the following areas:(1) the dendritic carbazole-based conjugated dendritic polymers were successfully synthesized via Suzuki coupling reaction.(2)the structure and thermal stability of these polyers would be tested. (3) Meanwhile, its performance (selectivity, sensitivity, interference resistance) of ion recognition was systematically studied. (4) the polymer materials used as mercury ion-test strips were investigated. It was expected to obtain excellent performance of the mercury ion optical probe materials.

汞离子作为一类严重剧毒性污染物质，对生态环境系统和人体具有严重的危害，如何能有效的检测汞离子已引起了科研工作者大量的关注。传统的检测方法有原子光谱法，诱导耦合等离子色谱，电化学法等。但是，这些检测大多需要昂贵的设备仪器，并且需要专业的技术人员以及娴熟的操作。光学探针尤其是应用共轭聚合物作为光学探针应用简单的紫外光谱和荧光光谱仪，可以很灵敏快速的对汞离子进行识别检测。在前期已研究了直链型咔唑类共轭聚合物可作为光学探针检测汞离子，但这种树枝状的咔唑类共轭聚合物作为汞离子光学探针还未曾报道。为了进一步提高探针对汞离子的检测选择性、灵敏性、抗干扰性，本课题从以下方面进行研究: (1) 通过Suzuki偶合反应，合成树枝状咔唑类共轭聚合物；(2)进行对所合成聚合物进行结构表征和热稳定性测试；(3)对Hg2+进行选择性、灵敏性和抗干扰性实验。（4）进行汞离子试纸实验。预期得到优异性能的汞离子光学探。

汞离子荧光探针是近期研究的热点，但大多报道是小分子汞离子探针。申请者在前期研究了直链型咔唑类共轭聚合物可作为光学探针检测汞离子。，本项目在前期研究的基础上对树枝状咔唑类共轭聚合物进行离子识别研究。分别合成了不同支化程度的含咔唑基的共轭聚合物，并对汞离子的响应性进行了研究，发现支化度相对低的含咔唑基共轭聚合物对汞离子识别灵敏性较高，可达到3.5 X 10 -8M数量级,同时对汞离子的检测的选择性较为专一，其它离子几乎对其检测不产生干扰。发现其它含氮基团如噻吩基的引入会对汞离子的检测起到负面影响，检测灵敏度的下降，选择性变差。支化程度高的聚合物对汞离子的检测灵敏度和选择性变差。该研究为合成高灵敏性、选择性的的共轭聚合物荧光探针提供理论支持。