从形状持久的橄酸盐宏观循环中获得水模拟的跨膜纳米孔.
Hongkwan Cho1, Lakmini Widanapathirana, Yan Zhao
1Department of Chemistry, Iowa State University, Ames, Iowa 50011-3111, USA.
Journal of the American Chemical Society
|December 15, 2010
概括
宏环氧化酸盐通过吸引水,在脂质膜中自我组装成纳米孔,从而抵制典型的疏水效应. 这种组合令人惊地增强了像葡萄糖和马尔托糖这样的分子的膜透性.
科学领域:
- 生物物理化学 生物物理化学
- 膜生物物理学 膜生物物理学
- 超分子化学 超分子化学
背景情况:
- 疏水性相互作用通常不利于疏水性环境中的自我组装.
- 宏环氧酸盐是具有潜在自组合特性的化合物.
- 脂质膜对分子运输构成一种疏水性屏障.
研究的目的:
- 为了研究脂质膜中宏环氧酸盐的自我组装行为.
- 了解水分子在这种自我组装过程中的作用.
- 探索这种自组装对膜透性和运输的影响.
主要方法:
- 在脂质膜中纳入宏环性橄胆酸盐.
- 观察自我组装成跨膜纳米孔的过程.
- 测量各种水友性分子 (葡萄糖,马尔托特) 的膜透性.
- 评估胆固醇对膜性质和运输的影响.
主要成果:
- 宏循环的寡聚合物通过在疏水膜内模拟聚合的水分子,自我组装成纳米孔.
- 这种自我组装过程是由一个不寻常的,反直觉的疏水效应驱动的.
- 膜对葡萄糖的透性随着胆固醇的加入而显著增加.
- 循环胆酸三聚合物对马尔托的透性比对葡萄糖的透性高.
结论:
- 疏水环境中的水聚合可以推动宏循环的自我组装成为功能性纳米孔.
- 这种自我组装机制导致膜传输特性发生意想不到的变化.
- 胆固醇可以增强含有橄酸盐的膜的透性,与其通常的效果相反.
- 这些新型纳米孔的尺寸选择性需要进一步研究.
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