Li Yan, Ma Rujiang, Zhao Lizhi, Tao Qian, Xiong De'an, An Yingli, Shi Linqi
Key Laboratory of Functional Polymer Materials, Ministry of Education, and Institute of Polymer Chemistry, Nankai University, Tianjin 300071, China.
Langmuir. 2009 Mar 3;25(5):2757-64. doi: 10.1021/la803996b.
To mimic nanostructures assembled by biomolecules in organic cells and achieve precise self-assembly of block copolymers, a simple but valid way is introduced to quasi-quantificationally control the aggregation numbers (N(agg)) of polymeric micelles. A three-dimensional and closed microconfinement similar to a cell is constructed by W/O inverse emulsion as the spot for self-assembly of the pH-responsive block copolymer poly(ethylene glycol)-block-poly(4-vinylpyridine) (PEG-b-P4VP). The N(agg) values of the resulting polymeric micelles are effectively controlled by tuning the number of polymer chains encapsulated in isolated water pools. Micelles with different N(agg) values are successfully prepared and characterized by atomic force microscopy, transmission electron microscopy, and dynamic light scattering. When the number of polymer chains enclosed in a water pool (N(chain)) is less than the average N(agg) of normal micelles generated in bulk aqueous solution, the resultant aggregates formed in the confined spaces always have lower N(agg) as well as smaller sizes than the normal micelles do, while normal micelles predominantly form when N(chain) > N(agg) (normal micelle).
为了模拟生物分子在有机细胞中组装的纳米结构并实现嵌段共聚物的精确自组装，引入了一种简单但有效的方法来准定量控制聚合物胶束的聚集数（N(agg)）。通过W/O反相乳液构建了一种类似于细胞的三维封闭微限域环境，作为pH响应性嵌段共聚物聚（乙二醇）-嵌段-聚（4-乙烯基吡啶）（PEG-b-P4VP）的自组装场所。通过调节隔离水池中封装的聚合物链数量，可有效控制所得聚合物胶束的N(agg)值。成功制备了具有不同N(agg)值的胶束，并通过原子力显微镜、透射电子显微镜和动态光散射进行了表征。当水池中封装的聚合物链数量（N(chain)）小于本体水溶液中生成的正常胶束的平均N(agg)时，在受限空间中形成的聚集体的N(agg)总是低于正常胶束，且尺寸也更小，而当N(chain) > N(agg)（正常胶束）时，则主要形成正常胶束。
