Diffusion of Liquid Domains in Lipid Bilayer Membranes

Top Cited Papers
Publisher Website
Google Scholar
Abstract
We report diffusion coefficients of micron-scale liquid domains in giant unilamellar vesicles of phospholipids and cholesterol. The trajectory of each domain is tracked, and the mean square displacement grows linearly in time, as expected for Brownian motion. We study domain diffusion as a function of composition and temperature and measure how diffusion depends on domain size. We find mechanisms of domain diffusion which are consistent with membrane-dominated drag in viscous Lo phases and bulk-dominated drag for less viscous Lα phases. Where applicable, we obtain the membrane viscosity and report activation energies of diffusion.