A mechanism for reversible mesoscopic aggregation in liquid solutions
A mechanism for reversible mesoscopic aggregation in liquid solutions
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DOI：
10.1038/s41467-019-10270-5
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发表时间：
2019-05-30
影响因子：
16.6
通讯作者：
Lubchenko, Vassiliy
中科院分区：
文献类型：
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作者：
Chan, Ho Yin;Lubchenko, Vassiliy
蛋白质和其他分子的溶液表现出令人费解的、介观尺寸的富含溶质液体的内含物，远远超出了富含溶质相的稳定区域。这种介观尺寸与现有的异相涨落观点相冲突。在这里，我们系统地研究了一种微观机制，通过该机制，亚稳态富溶质相可以很容易地在液体溶液中成核。该机制的一个必要组成部分是溶质与其自身或其他分子形成长寿命的复合物。以这种非经典方式成核后，各个液滴不断生长，直到由于内部压力的伴随下降而变得机械不稳定，这种下降是由富溶质相的亚稳定性引起的。液滴的整体是稳态的。在新制备的溶液中，预计整体会以类似于传统奥斯特瓦尔德成熟的方式演化，在此期间较大的液滴以较小的液滴为代价生长。
Solutions of proteins and other molecules exhibit puzzling, mesoscopically sized inclusions of a solute-rich liquid, well outside the region of stability of the solute-rich phase. This mesoscopic size is in conflict with existing views on heterophase fluctuations. Here we systematically work out a microscopic mechanism by which a metastable solute-rich phase can readily nucleate in a liquid solution. A requisite component of the mechanism is that the solute form long-lived complexes with itself or other molecules. After nucleated in this non-classical fashion, individual droplets grow until becoming mechanically unstable because of a concomitant drop in the internal pressure, the drop caused by the metastability of the solute-rich phase. The ensemble of the droplets is steady-state. In a freshly prepared solution, the ensemble is predicted to evolve in a way similar to the conventional Ostwald ripening, during which larger droplets grow at the expense of smaller droplets.