疏水性水化动态的热特征
1Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, SE-22100 Lund, Sweden.
Journal of the American Chemical Society
|July 16, 2008
概括
疏水性水合水比散装水更少的冰样,挑战了"冰山"模型. 液化中的水旋动态与散装不同,尤其是在低温下.
科学领域:
- 物理化学 物理化学
- 生物物理化学 生物物理化学
背景情况:
- 疏水性水合会影响化学和生物过程.
- 在低温下,离极溶液附近的水的异常行为尚未完全理解.
研究的目的:
- 在疏水性水化中描述水的旋转动力学.
- 调查温度依赖的行为到243K.
主要方法:
- 使用核磁共振 (2H NMR) 放松.
- 研究了四种部分疏水性溶液:两种和两种.
主要成果:
- 水的旋转在水化中表现出较低的激活能量,而不是255K以下的散装.
- 疏水性水合水比散装水少冰,这与"冰山"模型相矛盾.
- 具有相反蛋白质稳定性效应的奥斯莫利特显示出类似的水动态.
结论:
- 溶液的几何约束决定了水化中的水动力学.
- 这些发现挑战了"结构温度"概念.
- 与其他光谱学方法相比,NMR结果对疏水水分的观点不同.
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