在两性树突组合中低于LCST的温度敏感过渡:宿主-客人影响
Jack M Fuller1, Krishna R Raghupathi, Rajasekhar R Ramireddy
1Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA.
Journal of the American Chemical Society
|May 23, 2013
概括
研究人员发现了新的低至关溶液温度 (LCST) 过渡在基于基的超分子组件中. 这种过渡发生在低于LCST的水平,显著改变了主机-客机特性和封装稳定性.
科学领域:
- 超分子化学 超分子化学
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
背景情况:
- 装饰着Oligo (乙烯基醇) 的超分子组件因其电荷中立性而受到重视,从而最大限度地减少非特异性相互作用.
- 这些组件表现出经过充分记录的低临界溶液温度 (LCST) 阶段过渡,在高温下与水溶液分离.
- 这些组件在LCST以下的行为仍然在很大程度上未被探索.
研究的目的:
- 为了研究在已知的LCST下面的基于oligo (乙烯基醇) 的超分子组件中存在和特征的温度诱导的过渡.
- 阐明这一LCST子转换对主机-客户属性的影响,包括客户封装和主机交换动态.
主要方法:
- 利用基于乙烯糖醇 (OEG) 的树枝来构建超分子组件.
- 研究了这些组件在水溶液中的温度依赖行为.
- 在不同的温度调节下,宿主-客房属性,客房封装稳定性和宿主交换动态的特征变化.
主要成果:
- 确定了一种以前未报告的LCST次过渡,发生在明显低于宏观LCST的温度下.
- 在这一次LCST过渡过程中观察到超分子组合的宿主-客房属性的实质性变化.
- 记录了与子-LCST过渡相关的客体封装和主体交换的稳定性和动态的变化.
结论:
- 基于Oligo ((乙烯基醇) 的超分子组件表现出次要的,亚LCST过渡,对它们的功能性质有重大影响.
- 这种子-LCST过渡极大地影响了客体封装和主体-客体相互作用,扩大了对这些系统热行为的理解.
- 这些发现揭示了通过子-LCST温度调节来控制超分子组装行为和宿主-客人化学的新可能性.
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