多金属介导DNA基分子导线电荷输运机理与功能研究

项目名称： 多金属介导DNA基分子导线电荷输运机理与功能研究

项目编号： No.21303072

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 刘海英

作者单位： 济南大学

项目金额： 25万元

中文摘要： DNA近年来成为构建纳米器件的理想候选材料，但天然DNA的导电性还不足以直接应用于分子器件，进行功能化修饰以提高其导电性现已引起广泛的研究兴趣。鉴于常规的单金属离子修饰易引起构型的扭曲，本项目设计一种新颖的多金属离子碱基对修饰方案，并将考察扩环修饰和金属化修饰的联合效果，旨在寻找更佳的DNA基分子导线的修饰结构。利用密度泛函并结合分子动力学模拟，表征所做修饰对DNA结构、电子及光谱性质的影响，从原子分子水平上揭示DNA导电性增强的内在原因；将DNA与电极相组装，通过电子输运理论，用可测的导电性指标反映所做修饰对DNA电荷输运性质的改进效果；明确修饰前后的电荷传输机理，阐明传输通道和载体；找出金属离子的种类及金属配体碱基对调控DNA导电性的规律，建立有效的修饰结构与分子导线功能之间的构效关系。该工作的开展将为设计新型的生物分子导线提供必要信息，同时也有助于更好地理解DNA中的电荷转移。

中文关键词： 电荷输运；电子性质；分子器件；DNA修饰；密度泛函

英文摘要： DNA is becoming a potential candidate material for constructing nanoelectronic devices. However, the natural DNA lacks sufficient electrical conductance for direct applications in molecular electronics. Therefore, it has aroused extensive interests in chemically functionalizing DNA to improve its conductivity currently. In this proposal, we will design a novel class of multi-metal-mediated base pairs in order to minimize the configuration distortion as compared to the case of single-metal modification. The combined effects of size expansion and metal doping will be especially investigated toward optimizing the modification scheme for the design of DNA-based molecular wires. The changes of the structural, electronic and spectral properties will be explored with a combination of density functional theory calculations and molecular dynamics simulation to reveal the intrinsic reasons at atomic and molecular levels for the enhancement of conductivity of the modified DNA compared with the natural one. The molecular junctions consisting of DNA and electrodes would be constructed and investigated. The improvement of the conductivity owe to the multi-metal-modification of DNA will be evaluated by some measurable parameters with electronic transport theory. The charge transport mechanisms of the native and the modified DN

英文关键词： charge transport；electronic properties；molecular device；modification of DNA；density functional therory