三嗪类树状有机荧光探针和螯合树脂的合成及应用

Fluorescence analysis is a very important and effective spectrochemical analysis method, and fluorescence probe has become an important means to study the interaction between molecules. Thus the design and synthesis of fluorescence probes which have some advantags such as high quantum yield, longer wavelength of excitation and emission, good solubility in water, and high selectivity of discernment have grasped much attention.Many chemists always devote themselves to design and synthesis various kinds fluorescent moleculars for sensing different guest molecules. Dendrimers are kinds of new-type ordered polymers with three-dimensional structure and have multi-functional branches which are joined the active groups like ionphore and chromophore by dendronized reaction.Triazine is a type of heterocyclic organic compounds, it is important to ring nitrogen organic chemical raw materials and have good electronic affinity,then many triazine compounds,such as s-triazine,cynuric chloride and melamine,could be used to construct many kinds of compounds by substitution reaction and condensation reaction for their well reaction activity and controll ability.So the triazine derivatives are good template molecules to build dendritic molecules which have potential nonlinear optical property.Also,its performance meets various requirements of ideal biology fluorescent probes. Then we can design a series of fluorescent probes which may contain the advantage of dendrimers and triazine compounds. Therefore, this project plan to use triazine derivatives as the research object, use the cynuric chloride，melamine and cyanuric acid as the starting materials to build dendritic fluorescent or chromophore compounds, and then use them for sensing and recognizing some important biomacromolecules (such as deoxyribonucleic acid, protein and sugar), anions (like pyrophosphate,fluoride and acetate anions ect.), metal ions(such as copper,zinc,lead and mercury ions) and so on, provides a new approach and theoretical basis for the development of fluorescence probe and chelating resins. At the same time，we will study high sensitive colour or fluorescnce assays of noble metal ions and enrichment of noble metal ions (like tantalum,niobium)by a relatively new method of analysis and want to make use of the rare metals effectively.This research project is of great worth and may produce better economic benefits,it also has the vital significance for protection our natural environment and ecological balance.

荧光分析法是一种十分重要且有效的光谱分析方法，荧光探针成为了研究分子间相互作用的重要手段之一。设计合成量子产率高、激发和发射波长长、水溶性好，对识别客体具有高选择性和高灵敏度识别能力的探针倍受关注。树状大分子是一类具有三维结构、高度有序的新型高分子材料，利用树枝化反应将三维结构的树枝分子与多个特定功能团连接起来, 形成多功能化树枝，实现检测的信号放大与提供多处识别结合位点，故可大大提高分析方法的灵敏度。三嗪衍生物其良好的反应活性和可控性，以此作为构建树状分子的优良模板，可制得非线性光学活性分子，其性能易满足生物体荧光探针的各项要求。为此，本课题拟以三嗪环为中心的母体为研究对象，以三聚氰氯、三聚氰胺和三聚氰酸等三嗪类化合物为模板分子构建树状分子荧光探针，应用于识别金属离子、生物大分子(如DNA、蛋白质、糖)及阴离子(如焦磷酸根、F-、H2PO4-、SCN-)；优选与金属离子结合力强的功能化树枝，构建新螯合树脂。

围绕计划项目书要求合成了三嗪类衍生物及席夫碱类衍生物，采用核磁、质谱及元素分析对其结构进行了鉴定。研究了此类物质的光谱性能与结构的构效关系，建立金属离子Cu、Hg荧光和比色分析法。其次，将纳米材料与有机配体结合，优化配体结构，制备功能化纳米材料，实现离子或分子的识别与传感。以纳米金、纳米银及量子点为载体，通过纳米材料表面配体与识别客体通过氢键结合、或竞争结合使纳米颗粒聚集或反聚集，产生明显的颜色变化，据此建立了测定牛奶中的三聚氰胺、SCN-、Cd2+、Cr3+、Hg2+等，其检测限分别到达nM 级别，均低于限量标准。上述方法均在可见光谱区域内产生明显的颜色变化，可实现裸眼检测，易于推广应用。代表性成果如下：.合成2种对二甲氨基苯甲酰胺席夫碱衍生物，识别基团分别为吡咯环和吲哚环，均可作为 “turn-on”型荧光探针检测Cu2+，即使存在高浓度的其它离子和化合物时，探针对Cu2+仍具有很高的选择性和灵敏度，探针与Cu2+的络合比为2:1，两者均可应用于细胞成像以及试纸化定量检测Cu2+。比较两者的分析参数可知，含吡咯的探针的识别研究介质中含水为40%，结合常数为2.98 ×1011 M−2；而含吲哚的为20%，结合常数为1.33×1010 M−2；对Cu2+ 的检测下限分别为0.32和0.64 nM；可能原因是由于吲哚环较吡咯环体积大，故其水溶性有所降低，与Cu2+结合常数也有所下降。Cu2+在细胞中荧光成像图谱十分清晰，说明探针可试用于生物环境检测，且荧光增强型在细胞成像中应用前景更好。.将变色酸、对氨基苯磺酸修饰于纳米银表面，构建了三聚氰胺比色分析法，方法检测限分别为36和10.6nM，均低于安全限量（婴儿奶粉中三聚氰胺的限量标准为：中国8uM,美国和欧盟20uM,加拿大1.2uM）；同时，将对氨基苯磺酸和对氯苯磺酸修饰于纳米金表面，同样获得了三聚氰胺的传感体系，其方法检测限分别为1.2和2.3nM。通过颜色变化和紫外吸收光谱变化均可实现三聚氰胺的定性和定量分析，对牛奶中常见的金属离子、糖类、氨基酸具有较好的抗干扰能力，成功的运用于实际牛奶样品的检测。其中以纳米金为载体的识别体系灵敏度和选择性都较纳米银的体系有明显改善，且抗盐效果更佳。