DNA与聚合物胶束之间的精确自组装及其应用

项目名称： DNA与聚合物胶束之间的精确自组装及其应用

项目编号： No.21334001

项目类型： 重点项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 陈道勇

作者单位： 复旦大学

项目金额： 310万元

中文摘要： 大分子的精确自组装是大分子自组装领域的难题。我们初步的研究结果表明，在单分散DNA与聚合物胶束的自组装体系中，通过控制自组装条件，可使得该自组装具有精确自组装的特征。该组装过程中，在理论上被认为是能量最优化的单分散串珠状结构首先形成，并同步演化，最后形成单分散核壳结构纳米线（环）。重要的是，在已知长度的不同单分散纳米线的表面上，长度及序列已知的DNA链以左手螺线管状精确缠绕，使得纳米线表面被缠绕区域上的每一个特定的点都相当于被DNA修饰上一个特定的碱基对，即纳米线表面的部分区域具有精确结构，该自组装具有精确自组装的特征。我们将用计算证明：该体系中，能量最优化结构形成的原因是由于最优化结构与亚稳态结构之间的能量差较大；精确结构的形成与最优化结构中的精确作用方式有关。我们将充分利用该组装体的特点开展应用研究，并基于组装体上的精确结构开展复杂结构的精确构筑，尝试建立在精确结构基础上的功能组装。

中文关键词： 纳米环;纳米线;精确自组装;功能自组装;结构剪裁

英文摘要： Precise self-assembly of macromolecules is still a difficult problem in the field of macromolecular self-assembly. Our preliminary study reveals that the self-assembly of monodisperse DNA and core-positive-charged polymeric micelles has the characteristic of precise macromolecular self-assembly when conditions for the assembly are deliberately controlled. During the self-assembly, the monodisperse beads-on-a-string structure, which is proved theoretically to be the structure of global minimum in energy, forms firstly. Then, different assembles with the beads-on-a-string structure evolve in a similar manner synchronically, finally into monodisperse core-shell structured nanofibers (nanorings). It is important that, in each of the resultant monodisperse nanofibers of a certain length, a DNA chain with a certain length and a known sequence distribution wraps the core precisely, adopting a left-handed solenoid conformation. As result, there is a 2 nm (the width of DNA chains) width solenoid district on the core surface where each point is modified with a specific base pair due to the wrapping by the DNA . We are going to prove with theoretical calculations that the formation of the globally optimal structure mainly results from the relatively big energy gap between the energy of the globally optimized structure and the metastable structures; the precise interactions in the globally optimized structure is responsible for the monodispersity and precise structure of the assembles. We will take efforts to find unique applications of such precisely structured assemblies, construct highly complex but highly regular structures and functionalize the assembles by fully taking advantage of the precise structure.

英文关键词： nanorings;nanofibers;precise self-assembly;funtional self-assembly;structure tailoring