Coarsening dynamics of domains in lipid membranes.
Coarsening dynamics of domains in lipid membranes.
复制标题
脂膜结构域的粗化动力学。
DOI：
10.1016/j.bpj.2013.06.013
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发表时间：
2013
影响因子：
3.4
通讯作者：
Keller,SarahL
中科院分区：
文献类型：
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作者：
Stanich,CynthiaA;Honerkamp-Smith,AureliaR;Putzel,GregoryGarbès;Warth,ChristopherS;Lamprecht,AndreaK;Mandal,Pritam;Mann,Elizabeth;Hua,Thien-AnD;Keller,SarahL
我们研究了直径在80 - 250μm之间的自由漂浮的巨大单层囊泡膜内微米级液域的等温扩散和生长。在快速温度淬火后，当膜通过可溶解性相变冷却时，出现域，从而形成共存的液相。在远离可溶解性临界点淬火的膜中，圆形结构域成核，然后在几秒钟内进展到后期粗化，其中结构域通过两种机制生长：1）液体结构域的碰撞和聚结，以及2）奥斯特瓦尔德熟化。这两种机制预计会产生相同的增长指数，α= 1/3，其中畴半径随时间α而增长。我们测得α= 0.28 ± 0.05，非常一致。在接近可渗透性临界点的膜中，膜中的两个液相是双连续的。在临界组成附近的淬火导致细长域的形态的快速变化。在这种情况下，我们测得α= 0.50 ± 0.16，与理论和模拟一致。
We investigate isothermal diffusion and growth of micron-scale liquid domains within membranes of free-floating giant unilamellar vesicles with diameters between 80 and 250μm. Domains appear after a rapid temperature quench, when the membrane is cooled through a miscibility phase transition such that coexisting liquid phases form. In membranes quenched far from a miscibility critical point, circular domains nucleate and then progress within seconds to late stage coarsening in which domains grow via two mechanisms 1), collision and coalescence of liquid domains, and 2), Ostwald ripening. Both mechanisms are expected to yield the same growth exponent,α= 1/3, where domain radius grows as timeα. We measureα= 0.28 ± 0.05, in excellent agreement. In membranes close to a miscibility critical point, the two liquid phases in the membrane are bicontinuous. A quench near the critical composition results in rapid changes in morphology of elongated domains. In this case, we measureα= 0.50 ± 0.16, consistent with theory and simulation.