弹性钢的反弹是由疏水效应驱动的.
Nour M Jamhawi1, Ronald L Koder2,3, Richard J Wittebort1
1Department of Chemistry, University of Louisville, Louisville, KY 40292.
概括
疏水效应,而不是回力,驱动脊椎动物的弹性质功能. 这一发现解释了弹性质的弹性和寿命,对动脉和肺部至关重要.
科学领域:
- 生物物理学的生物物理.
- 材料科学 材料科学 材料科学
- 生物化学 生化学
背景情况:
- 弹性是脊椎动物中重要的细胞外基质蛋白,为动脉,肺和皮肤等组织提供弹性.
- 其非凡的弹性,经历了数十亿个循环而没有被替换,是组织功能和寿命的关键.
- 长期以来,关于弹性的反弹机制的争论,无论是的还是其他,已经持续了五十年多.
研究的目的:
- 为了阐明弹性弹性反弹机制背后的主要驱动力.
- 研究水的排序和热力学特性在弹性质的功能中的作用.
- 挑战目前的热带反弹理论,并提出一个替代的机制.
主要方法:
- 使用了核磁共振 (NMR) 和热力学研究的联合方法.
- 在溶剂:蛋白界面上观察到水的排序,使用双量子2H NMR作为拉伸的函数.
- 通过在不同的力,温度和溶剂条件下测量弹性质的长度和体积进行了广泛的热力学分析.
主要成果:
- 证明在溶剂:蛋白界面上的水排序与弹性质拉伸成比例增加.
- 在拉伸时观察到热容量增加和内部能量减少,释放的热量超过了所做的工作.
- 热力学特征被辅溶剂改变,这些辅溶剂修改了疏水效应,支持其作用.
结论:
- 在生理条件下,疏水效应,而不是配置,是弹性质反弹的主要驱动因素.
- 这种机制解释了弹性质的特殊弹性和耐硬性,与不同.
- 由疏水效应驱动的反弹被认为是弹性质独特性质和寿命的根本来源.
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