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Domain Growth, Budding, and Fission in Phase Separating Self-Assembled Fluid Bilayers

Mohamed Laradji·P. B. Sunil Kumar
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Abstract

A systematic investigation of the phase separation dynamics in self-assembled multi-component bilayer fluid vesicles and open membranes is presented. We use large-scale dissipative particle dynamics to explicitly account for solvent, thereby allowing for numerical investigation of the effects of hydrodynamics and area-to-volume constraints. In the case of asymmetric lipid composition, we observed regimes corresponding to coalescence of flat patches, budding, vesiculation and coalescence of caps. The area-to-volume constraint and hydrodynamics have a strong influence on these regimes and the crossovers between them. In the case of symmetric mixtures, irrespective of the area-to-volume ratio, we observed a growth regime with an exponent of 1/2. The same exponent is also found in the case of open membranes with symmetric composition.

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Mohamed Laradji, P. B. Sunil Kumar. 2006-02-02. Domain Growth, Budding, and Fission in Phase Separating Self-Assembled Fluid Bilayers. https://doi.org/10.1063/1.2102894

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