writer：Ming Wu, Yutian Zhu, Wei Jiang
keywords：多隔室胶束, 静电场, 空间序列解组装, 按时序释放, 嵌段共聚物
source：期刊
specific source：Angewandte Chemie International Edition, 2018, 57(14), 3578-3582
Issue time：2018年

摘要：聚合物可通过自组装自发形成具有有序结构的多种胶束，这些胶束通常因体系落入最低自由能点（亚稳态）而相对稳定，一般不能自发解组装。外部刺激（如温度、pH、光或电压）可用于使已形成的聚合物胶束解组装，是实现聚合物胶束靶向递送和可控释放功能的重要途径，但顺序或选择性解组装仍是一大挑战。本文报道了一种新颖的静电场控制多隔室胶束（MCPs）空间序列解组装策略。该策略通过空间序列解组装，可实现负载物种按时间顺序释放，为MCPs进一步功能化提供了简便有效的途径，在药物递送和组合催化方面具有潜在应用。实验通过将1 wt%聚苯乙烯-b-聚2-乙烯基吡啶-b-聚环氧乙烷（PS770-b-P2VP134-b-PEO91）溶于四氢呋喃（THF）/水混合物制备MCPs，并在平行板电极间施加直流电压，观察到在静电场作用下小球形胶束依次从MCPs上脱离。

Abstract：Polymers can spontaneously form various micelles with well-ordered structures by self-assembly. These micelles are relatively stable since the system falls into minimum free-energy points (i.e., metastable states), and in general they cannot be disassembled spontaneously due to the existence of energy barriers. External stimuli (such as temperature, pH value, light or voltage) can be employed to disassemble the formed polymer micelles, representing an important way to realize functions such as targeted delivery and controlled release for polymer micelles. Nevertheless, sequential or selective disassembly is still a major challenge and seldom reported. Here, we reported a novel electrostatic field-controlled disassembly of multicompartment micelles (MCPs) in spatial sequence. More interestingly, this strategy allows us to realize release of the loaded species in chronological order through disassembly in spatial sequence. Our findings provide a facile yet effective strategy for further functionalization of MCPs, which are potentially useful in drug delivery and combination catalysis. The MCPs comprising sequences of repeated elemental discoid parts connected by fasciculus were prepared through directly dissolving 1 wt% polystyrene-block-poly(2-vinyl pyridine)-block-poly(ethylene oxide) (PS770-b-P2VP134-b-PEO91) in tetrahydrofuran (THF)/water mixture, and the consequent departure of small spherical micelles from MCPs under the electrostatic field could be clearly observed.

论文链接：https://doi.org/10.1002/anie.201712794