具有UCST相分离行为的高排序多
Sotaro Kuroyanagi1, Naohiko Shimada1, Shota Fujii2
1Department of Life Science and Technology , Tokyo Institute of Technology , 4259 B-57 , Nagatsuta, Yokohama 226-8501 , Japan.
Journal of the American Chemical Society
|January 1, 2019
概括
立体规律性显著影响热敏聚合物的行为. 同人基聚与种族基聚相比,具有更高的相分离温度和独特的聚合模式,为高级生物材料提供了洞察力.
科学领域:
- 聚合物科学
- 生物材料科学
- 材料化学
背景情况:
- 热敏聚合物对于药物输送和组织工程至关重要.
- 聚合物中的上临界溶液温度 (UCST) 行为尚未得到充分研究.
- 了解立体规律对UCST的影响是材料设计的关键.
研究的目的:
- 调查聚固态规律性对上临界溶液温度 (UCST) 行为的影响.
- 为了比较 homochiral 和 racemic 基于 citrulline 的聚分离和聚合.
- 探索这些热敏聚合物的结构基础和生物降解性.
主要方法:
- 具有不同立体规律性的多甲合素 (POC) 变体的合成和表征.
- 使用热分析测量相隔温度 (Tps).
- 通过循环二重化 (CD) 和小角度X射线散射 (SAXS) 进行结构分析.
主要成果:
- 同人体中的多甲合甲素 (PlOC) 和多甲合甲素 (PdOC) 的Tps比血型多甲合甲素 (PdOC) 高.
- PdlOC显示了液态到合物相分离,而PlOC和PdOC则形成了类似固体的聚合物.
- 均POC采用阿尔法螺旋结构并组装成六角格子,由尿素群相互作用驱动.
结论:
- 立体规律性决定了UCST的行为,相分离模式和基于的多的结构组织.
- 在同质性POC中观察到的螺旋折叠和六角组件是由于悬浮的尿素群相互作用.
- 分相结构影响生物降解性,突显了这些UCST类型聚合物的可调节生物材料应用的潜力.
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