School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, 639798 Singapore.
Langmuir. 2014 Mar 4;30(8):2152-60. doi: 10.1021/la404582n. Epub 2014 Feb 21.
We have investigated the effect of freeze-thaw (FT) pretreatment on the adhesion and rupture of extruded vesicles over a wide range of vesicle sizes. To characterize the size distributions of vesicles obtained with and without FT pretreatment, dynamic light scattering (DLS) experiments were performed. The interaction between extruded vesicles and a silicon oxide substrate was investigated by quartz crystal microbalance with dissipation (QCM-D) monitoring, with a focus on comparative analysis of similar-sized vesicles with and without FT pretreatment. Under this condition, there was a smaller mass load at the critical coverage associated with untreated vesicles, as compared to vesicles which had been subjected to FT pretreatment. In addition, the rupture of treated vesicles generally resulted in formation of a complete planar bilayer, while the adlayer was more heterogeneous when employing untreated vesicles. Combined with kinetic analysis and extended-DLVO model calculations, the experimental evidence suggests that the differences arising from FT pretreatment are due to characteristics of the vesicle size distribution and also multilamellarity of an appreciable fraction of untreated vesicles. Taken together, our findings clarify the influence of FT pretreatment on model membrane fabrication on solid supports.
我们研究了在广泛的囊泡尺寸范围内，冻融（FT）预处理对挤出囊泡的粘附和破裂的影响。为了表征经过和未经 FT 预处理获得的囊泡的大小分布，进行了动态光散射（DLS）实验。通过石英晶体微天平耗散（QCM-D）监测研究了挤出囊泡与氧化硅基底之间的相互作用，重点是对具有和不具有 FT 预处理的相似大小的囊泡进行比较分析。在这种条件下，与未经处理的囊泡相比，与未处理的囊泡相关的临界覆盖物的质量负载较小。此外，处理过的囊泡的破裂通常导致形成完整的平面双层，而使用未经处理的囊泡时，吸附层则更加不均匀。结合动力学分析和扩展-DLVO 模型计算，实验证据表明，FT 预处理引起的差异归因于囊泡大小分布的特征以及相当一部分未经处理的囊泡的多层性。总之，我们的研究结果阐明了 FT 预处理对固体支持物上模型膜制备的影响。
