Lateral stress relaxation and collapse in lipid monolayers.
Lateral stress relaxation and collapse in lipid monolayers.
复制标题
脂质单层的横向应力松弛和塌陷。
作者：
Pocivavsek,Luka;Frey,ShelliL;Krishan,Kapilanjan;Gavrilov,Kseniya;Ruchala,Piotr;Waring,AlanJ;Walther,FransJ;Dennin,Michael;Witten,ThomasA;Lee,KaYeeC
在空气/水界面处的表面活性剂通常经受机械应力，因为它们占据的界面面积减小。在这些系统中，应力松弛的最好表征形式是从较低密度相到较高密度相的一级相变。在这里，我们研究应力松弛脂质单层发生化学相变已经用尽。在这些高度压缩的状态下，单层经历称为塌陷的全局机械弛豫。通过研究四种不同类型的单分子膜，我们确定的崩溃模式是最密切相关的面内刚度。我们通过分析在许多长度尺度上的平面形态来表征单层的刚性。更刚性的单分子层通过类似于弹性膜的硬弹性模式在平面外塌陷，而更软的单分子层通过剪切在平面内松弛。
Surfactants at air/water interfaces are often subjected to mechanical stresses as the interfaces they occupy are reduced in area. The most well characterized forms of stress relaxation in these systems are first order phase transitions from lower density to higher density phases. Here we study stress relaxation in lipid monolayers that occurs once chemical phase transitions have been exhausted. At these highly compressed states, the monolayer undergoes global mechanical relaxations termed collapse. By studying four different types of monolayers, we determine that collapse modes are most closely linked to in-plane rigidity. We characterize the rigidity of the monolayer by analyzing in-plane morphology on numerous length scales. More rigid monolayers collapse out-of-plane via a hard elastic mode similar to an elastic membrane, while softer monolayers relax in-plane by shearing.