AFM investigations of phase separation in supported membranes of binary mixtures of POPC and an eicosanyl-based bisphosphocholine bolalipid.
AFM investigations of phase separation in supported membranes of binary mixtures of POPC and an eicosanyl-based bisphosphocholine bolalipid.
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AFM 对 POPC 和基于二十烷基的双磷酸胆碱 bolipid 的二元混合物的支撑膜中的相分离进行研究。
DOI：
10.1021/la904532s
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Johnston,LindaJ
中科院分区：
文献类型：
--
作者：
Mulligan,Kirk;Brownholland,David;Carnini,Anna;Thompson,DavidH;Johnston,LindaJ
Supported membranes prepared from binary mixtures of DOPC and the bolalipid C20BAS have been examined by atomic force microscopy (AFM). The supported membranes are phase separated to give a thicker DOPC-rich phase and a thinner bolalipid-rich phase for a range of lipid compositions. These results confirm an earlier prediction from mean field theory that phase separation is the thermodynamically stable state for membranes containing approximately equimolar C20BAS and double chain monopolar lipids with chain lengths exceeding 15 carbons. Hydrophobic mismatch between the monopolar lipid hydrocarbon chains and the membrane spanning bolalipid chains was suggested to provide the driving force for phase separation. The AFM results also show that the morphology of the mixed POPC:C20BAS supported membranes varies significantly with the conditions used to prepare the vesicles and supported membrane samples. The complex membrane morphologies observed are attributed to the interplay of several factors, including a compositionally heterogeneous vesicle population, exchange of lipid between the vesicle solution and solid substrate during formation of the supported membrane, and slow equilibration of domains due to pinning of the lipids to the solid support.
