DNA介导钌配合物包覆纳米颗粒的新型光电复合材料研究

DNA has the unique molecular structure, which has potential to be employed as a mediator for the encapsulation of ruthenium complexes possessing excellent optoelectronic properties. The novel core-shell structured ruthenium complex-covered nanocomposite materials mediated by DNA have great potential for applications in the field of photo-electrochemical anlaysis. The ruthenium complex-DNA film is self-assembled on the substrate surfaces based on their interactions; The core-shell structured nanocomposite materials with the unique optoelectronic properties are prepared by the self-assembled encapsulation of ruthenium complex-DNA film on the nanoparticles such as CdS and ZnS; The optoelectronic properties of ruthenium complex-DNA film and nanocomposites are investigated by in situ electrochemical laser-microscope technique, as well as the electrochemical reactions upon light radiation and the electrochemistry-induced photoluminescence. Furthermore, the luminescence mechanism of the prepared nanocomposite materials is studied by exploring the effects of various infactors on the photoelectric properties, viz. the structrures of ruthenium complexes and DNA-sequence, metal ions, quencher, DNA hydrolysis enzyme, surfactant, ion strength and temperature. On the basis of controllable optoelectronic properties, the molecular light-switch and photo-electrochemical sensor are fabricated.

基于钌配合物良好的光电特性和DNA独特的分子结构，以DNA作媒质，调控钌配合物对纳米颗粒的包覆，制备核壳结构新型纳米复合材料，发展其在光电分析中的应用。利用溶液中钌配合物与DNA间的相互作用，研究其在固体表面的自组装成膜；利用钌配合物-DNA自组装成膜，包覆硫化镉和硫化锌等纳米粒子，制备光电性能独特的复合材料；利用自身发展的电化学原位激光-显微镜技术，研究钌配合物-DNA膜及膜包覆纳米颗粒的光电特性、光诱导下的电化学反应和电诱导下的光致发光性能；通过研究配合物结构、DNA序列结构、金属离子、猝灭剂、DNA水解酶、表面活性剂、离子强度、温度等对复合材料光电化学性能的影响，阐明该类复合材料的发光机制，并有目的地调控复合材料的光电特性，构筑分子光开关和光电化学传感器。

基于DNA独特的分子结构和钌配合物的良好光电特性及相互作用，以DNA为媒质，通过调控钌配合物对纳米颗粒的包覆，构筑了新型的光电复合材料，发展了其在一些内源分子检测与利用中的应用，这也为浓缩DNA与其它分子间的相互作用研究提供了新途径。“V-型”双钌配合物被发现能诱导DNA浓缩，过程中伴随着B-DNA向Z-DNA构象的转变，而增大NaCl浓度则有利于DNA-钌配合物复合物的解离；DNA-钌配合物膜不仅对溶解氧显示出可逆的光开关特性，而且膜中DNA具有很好的抗氧化能力； 键合到DNA沟面上的钌配合物能诱导B-DNA向Z-DNA构象转变，导致其对氧气的传感速率降低了33%；阐明了金属离子和外加电场对纳米半导体电极上DNA和BSA介导钌配合物的发光淬灭机理及与光伏响应间的协同关系。