Hybrid membranes of lipids and diblock copolymers: From homogeneity to rafts to phase separation

Ssu Wei Hu, Chun Yen Huang, Heng Kwong Tsao, Yu Jane Sheng

Research output: Contribution to journalArticlepeer-review

19 Scopus citations

Abstract

Hybrid lipid-polymer vesicles can integrate benefits of liposomes and polymersomes. In this work, the phase behavior of hybrid membranes containing lipids and diblock copolymers is explored by dissipative particle dynamics simulations. The influences of lipid unsaturation and thickness mismatch between lipids and polymers are considered. The transition from the mixing state (homogeneous distribution) to the demixing state (formation of bilayered lipid-rich domains) is always observed as the lipid concentration (φl) exceeds a critical value, which increases with the degree of unsaturation. It is found that phase separation is driven by weak energy incompatibility between the hydrophobic segments of lipids and polymers. When the effect of thickness mismatch becomes significant, the occurrence of the demixing state is retarded, and monolayer lipid rafts emerge before phase separation. Lipid fluidity associated with the physical state of a hybrid membrane can be characterized by lateral lipid diffusivity (Dl). In the polymer-rich membrane, Dl is higher in the mixing state, but decreases generally with φl due to lipid-lipid interactions and interdigitation.

Original languageEnglish
Article number012403
JournalPhysical Review E - Statistical, Nonlinear, and Soft Matter Physics
Volume99
Issue number1
DOIs
StatePublished - 3 Jan 2019

Fingerprint

Dive into the research topics of 'Hybrid membranes of lipids and diblock copolymers: From homogeneity to rafts to phase separation'. Together they form a unique fingerprint.

Cite this