与脂膜相关的界面水结构通过相敏振动总频生成光谱学研究
Xiangke Chen1, Wei Hua, Zishuai Huang
1Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA.
Journal of the American Chemical Society
|August 12, 2010
概括
界面水分子与脂尾巴对齐,净负脂质导致更强的水排序. 与脂质的结合破坏了在接口上的这种水的排序.
科学领域:
- 物理化学 物理化学
- 生物物理学的生物物理.
- 表面科学是一门学科.
背景情况:
- 了解水界面结构对于生物过程至关重要.
- 脂形成细胞膜,它们与水的相互作用影响了细胞膜的功能.
研究的目的:
- 研究水分子在各种脂/水接口的方向和排序.
- 为了比较不同脂组的水结构能力.
主要方法:
- 使用相位敏感的振动总频率生成 (SFG) 谱法.
- 这项研究检查了由二聚基醇 (DPPC),二聚基乙胺 (DPPE),二聚基酸盐 (DPPA),二聚基糖醇 (DPPG) 和二聚基-l-氨酸 (DPPS) 形成的接口.
主要成果:
- 在所有研究的脂质中,界面水分子始终以其双极指向脂尾巴的方向定位.
- 与净负脂 (DPPA, DPPG, DPPS) 相比,基脂 (DPPC, DPPE) 的水导向效应较弱.
- 发现与脂质酸盐组结合的离子的存在降低了界面水分子的排序.
结论:
- 脂组的静电潜力显著决定了水的界面结构.
- 脂质头组电荷影响水的排序程度,净负电荷促进更大的排序.
- 阴离子结合可以调节脂接口的水化层,影响分子相互作用.
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