DNA-不对称大环席夫碱配位聚合物的自组装、结构和性质研究

DNA has recently been emerged as a versatile material for constructing molecular devices for its intrinsic characteristics,including programmability and self-organization . Herein, a new method would be introduced about the development of self-assembly asymmetric macrocycle Schiff-base coordination polymer by the hydrogen bond interactions, which would provide a new idea for the synthesis of asymmetric molecule. The asymmetric macrocycle Schiff-base complexes can be systhesized step by step using DNA template, and linked by the conjugated ligands at the activated axial position of the metal ions to form metal - organic polymers, which are characterized by gel electrophoresis, circular dichroism, UV-vis spectrum and mass spectrum. The properties of the polymers would be studied by fluorescence spectrum, electric conductivity and variable temperature magnetic susceptibility respectively, according to the characteristic of the metal ions and the bridge ligands . The influence of the metal ions, substituted groups and pH values on the properties of the polymers would be studied. The relationship between the structure and the property would be summarized based on the experimental results. The influence of the polymers on the properties of DNA would also be studied.

由于具有可编程性和自我识别的特性，DNA分子已成为构筑纳米器件的一种重要材料。本项目利用DNA碱基的精确配对和序列可编的特性，发展一种利用DNA单链间的氢键相互作用自组装不对称大环席夫碱配位聚合物的新方法，为不对称合成提供新的思路。利用DNA模板效应，首先分步合成不对称大环席夫碱配合物。然后活化金属离子轴向位置配位点，利用具有共轭结构的配体进行桥联，构筑一维或二维不对称大环席夫碱配位聚合物，并运用凝胶电泳、圆二色谱、紫外-可见光谱和质谱对聚合物的结构进行表征。根据金属离子及桥联配体的特性，利用荧光光谱、电导率及变温磁化率对聚合物的光、电、磁性质进行分类研究。通过本项目的研究，探索金属离子种类及浓度、取代基种类及位置、pH值等对聚合物性质的影响，探索聚合物结构和性质之间的关系，探索聚合物对DNA性质的影响。

DNA单链通过分子间氢键作用可自组装成稳定的具有手性螺旋结构的多链分子。利用DNA模板效应，通过对温度、浓度、溶剂等反应条件的摸索，成功合成得到不对称大环席夫碱配合物。通过活化金属离子轴向配位点，利用具有共轭结构的桥联配体的键合，构筑得到不对称大环席夫碱配位聚合物。运用凝胶电泳和HPLC对产物进行纯化和分离，通过圆二色谱、紫外 – 可见光谱和质谱对配合物的结构进行表征。根据配合物的荧光光谱，研究了DNA模板、金属离子类型、金属离子浓度、配合物的结构、体系的pH对其发光性质的影响，为新型生物探针分子的合成提供科学依据。