多相聚合物溶液体系受限于软膜内的自组装行为研究（四）

项目名称： 多相聚合物溶液体系受限于软膜内的自组装行为研究（四）

项目编号： No.91227121

项目类型： 重大研究计划

立项/批准年度： 2013

项目学科： 高分子科学

项目作者： 李宝会

作者单位： 南开大学

项目金额： 75万元

中文摘要： 管膜结构普遍存在于真核细胞中，然而，其形成机制和稳定性是尚未完全解决的重要问题。近期的实验研究发现，将仿生膜放到右旋糖苷和聚乙二醇溶液体系中溶胀，可形成包含该两相溶液的软膜体系；通过调节体系的渗透收缩、温度等可诱导该体系出现多种现象，如从部分润湿到完全润湿的转变、发芽和膜管的形成等。因此，这种发生在包含两相溶液的软膜体系中的相分离可作为研究在细胞拥挤环境中出现的管膜结构的模型系统。本项目拟采用模拟退火等方法，围绕多相高分子溶液体系受限于软膜内的自组装行为开展研究。一方面，我们将利用不良溶剂提供软受限环境，开展在软受限环境下多相高分子溶液体系自组装行为的研究。另一方面，在借鉴Helfrich 模型的基础上，我们将发展合适的模型以研究多相高分子溶液体系受限于软膜内自组装行为。探索体系出现发芽转变的条件，揭示发芽转变的微观机制。本项目的成果将有助于理解相关的细胞机制，如内吞和胞外分泌作用等。

中文关键词： 自组装；嵌段共聚物；软受限；模拟退火方法；多相高分子溶液体系

英文摘要： Tubular membrane structures are widespread in eukaryotic cells, but the mechanisms underlying their formation and stability are not well understood. Recently, biomimetic membranes exposed to aqueous two-phase system have been introduced experimentally. They are found to exhibit a number of interesting and surprising phenomena, such as partial to complete wetting transitions, budding, and membrane tube formation. These aqueous phase separation in the closed environment of biomimetic membrane vesicles can serve as a model system for tubular membrane structures in cells. In this project, we will investigate the self-assembly of aqueous multi-phase-polymer system confined in soft membranes using simulated annealing and other methods. On one hand, we will study the self-assembly of aqueous multi-phase-polymer system under soft confinement realized by the formation of polymer droplets in a poor solvent environment. On the other hand, based on Helfrich model, we will develop a new model. Using this model, we will investigate the self-assembly of aqueous multi-phase-polymer system confined in soft membranes. We will find out the parameter region where budding transition occurs, and elucidate the microscopic mechanism of budding. The results of this project would be helpful for understanding related cellular mechanisms,

英文关键词： Self-assembly；block copolymers；soft confinement；simulated annealing；aqueous multi-phase-polymer system