液滴中液泡形成的物理机制
Physical Mechanism of Vacuole Formation in Liquid Droplets
AI总结：
研究液滴中液泡形成的物理机制，通过理论证明其由局部失稳形成，利用非平衡热力学开发理论框架确定控制条件，结果有助于促进液泡化及实现多隔室工程功能。
AI中文摘要：
在各种实验系统的液滴中都观察到了液泡，从由蛋白质和RNA组成的生物分子凝聚物到由带电聚合物或合成纳米星形成的合成凝聚层。这些液泡是液滴物质耗尽的长寿命区域，其形成令人困惑，因为界面面积的增加在热力学上是不利的。我们通过理论表明，液泡通过一种通用机制形成：液滴内的局部失稳。我们在几个实验相关场景中证明了这一机制，包括温度猝灭以及与液滴内部或外部发生的化学过程耦合的液滴。我们利用非平衡热力学开发了一个理论框架，确定了控制液泡是否形成以及液泡能有多大的物理化学条件。我们的结果提出了促进液泡化的分子设计和化学途径，能够实现具有工程功能（如增强表面催化和隔室裂变）的多隔室形成。
英文摘要：
Vacuoles have been observed in liquid droplets across variety of experimental systems, ranging from biomolecular condensates composed of proteins and RNA, to synthetic coacervates formed by charged polymers or synthetic nanostars. These vacuoles are long-lived domains depleted of droplet material, and their formation is puzzling because the associated increase in interfacial area is thermodynamically unfavorable. Using theory, we show that vacuoles form through a generic mechanism: a local spinodal instability within the droplet. We demonstrate this mechanism in several experimentally relevant scenarios, including temperature quenches and droplets coupled to chemical processes occurring either inside or outside the droplet. Using non-equilibrium thermodynamics, we develop a theoretical framework that identifies the physicochemical conditions controlling whether vacuoles form and how big vacuoles can become. Our results suggest molecular designs and chemical pathways that promote vacuolation, enabling multi-compartment formation with engineered functions such as enhanced surface catalysis and compartment fission.
