在分子疏水界面上水的结构转化
Joel G Davis1, Kamil P Gierszal, Ping Wang
1Purdue University, Department of Chemistry, West Lafayette, Indiana 47907, USA.
Nature
|November 23, 2012
概括
疏水性水解是因为疏水性水解
科学领域:
- 水-溶解物相互作用
- 生物物理化学 生物物理化学
- 化学物理 化学物理
背景情况:
- 疏水性水合对于蛋白质折叠等生物过程至关重要.
- 从历史上看,水化被模拟为酸盐水合物.
- 最近的研究强调了长度尺度在疏水性水合中的重要性.
研究的目的:
- 为了研究疏水性水化的结构和动态特性.
- 探索温度和链条长度对水溶液周围水结构的影响.
- 使用拉曼散射绘制水化的振动光谱特征.
主要方法:
- 结合极化,同位素和温度依赖的拉曼散射.
- 多变量曲线分辨率 (拉曼-MCR) 分析.
- 在0-100°C的温度范围内研究从甲醇到乙醇的线性酒精.
主要成果:
- 在低温下,水化体表现出增强的四面体水序,与散装水相比,较少的弱键.
- 这种有序的结构随着温度的增加而减少.
- 对于长于~1nm的疏水链,在更高的温度下,会出现具有较弱键的更混乱的结构.
结论:
- 这些发现支持了热诱导的水结构转变在疏水性水化中的概念.
- 观察结果与在特定长度尺度 (~1 nm) 上预测的疏水性交叉现象一致.
- 这项研究提供了有关水分子周围水结构温度依赖行为的详细见解.
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