Foo Ji-Jinn, Chan Vincent, Liu Kuo-Kang
Tissue Engineering Laboratory, School of Mechanical and Production Engineering, Nanyang Technological University, Singapore 639798.
Ann Biomed Eng. 2003 Nov;31(10):1279-86. doi: 10.1114/1.1616934.
The role of osmotic pressure on the geometry of adherent liposome remains an intricate question in the mechanics of supramolecular structures. In this study, confocal reflection interference contrast microscopy in combination with cross-polarized microscopy was applied to probe the geometry of deformed liposome on fused silica substrates through the determination of a vesicle-substrate separation profile. In parallel, a theoretical model which describes the large deformation of the lipid bilayer membrane under both out-plane bending and in-plane shear forces is developed. Then, the global deformation geometry of the adherent liposome is rigorously compared with our experimental data. It is shown that the adhesion contact area increases in dimension, the liposome volume decreases, and the vesicle height decreases under the reduced osmotic pressure. The coupling of experimental data and a modified theoretical framework of the adherent liposome provides a more explicit result in comparison with previous studies and demonstrates the possibility of modeling the change of liposome mechanics under the influence of osmosis.
渗透压对附着脂质体几何形状的作用在超分子结构力学中仍然是一个复杂的问题。在本研究中，共聚焦反射干涉对比显微镜与交叉偏振显微镜相结合，通过确定囊泡 - 底物分离轮廓来探测融合石英基板上变形脂质体的几何形状。同时，建立了一个理论模型，该模型描述了脂质双分子层膜在面外弯曲和面内剪切力作用下的大变形。然后，将附着脂质体的整体变形几何形状与我们的实验数据进行了严格比较。结果表明，在渗透压降低的情况下，粘附接触面积增大，脂质体体积减小，囊泡高度降低。与先前的研究相比，实验数据与附着脂质体的改进理论框架的结合提供了更明确的结果，并证明了对渗透作用影响下脂质体力学变化进行建模的可能性。
