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Unbinding Transition Induced by Osmotic Pressure in Relation to Unilamellar Vesicle Formation

N. L. Yamada·M. Hishida·H. Seto·K. Tsumoto·T. Yoshimura
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Abstract

Small-angle X-ray scattering and phase-contrast microscopy experiments were performed to investigate the effect of the osmotic pressure on vesicle formation in a dioleoylphosphatidylcholine (DOPC)/water/NaI system. Multi-lamellar vesicles were formed when a pure lipid film was hydrated with an aqueous solution of NaI. On the other hand, uni-lamellar vesicles (ULVs) were formed when a lipid film mixed with an enough amount of NaI was hydrated. To confirm the effect of the osmotic pressure due to NaI, a free-energy calculation was performed. This result showed that the osmotic pressure induced an unbinding transition on the hydration process, which resulted in ULV formation.

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N. L. Yamada, M. Hishida, H. Seto, K. Tsumoto, T. Yoshimura. 2006-07-26. Unbinding Transition Induced by Osmotic Pressure in Relation to Unilamellar Vesicle Formation. https://doi.org/10.1209/0295-5075%2F80%2F48002

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