Shape Deformation and Phase Separation Dynamics of Two-Component Vesicles

Abstract

We numerically study dynamics of shape deformations of vesicles resulting from intramembrane phase separation. At off-critical compositions resultant vesicle shapes closely resemble the echinocytosis of red blood cells, while at the critical composition a bicontinuous domain structure emerges. The coarsening process of domain structures on such a deformable surface is considerably slower than that on a rigid surface. The total length of domain boundaries $N_{\mathrm{DB}}$ decreases as $t^{-1/3\mathrm{}}$ for the rigid sphere, whereas in the present system $N_{\mathrm{DB}}\simeq t^{-z}$ $\left(z\simeq 0.1\right)$ at the late stage due to the coupling between the shape and the phase separation.