title: Coarsening dynamics of domains in lipid membranes.
abstract: We investigate isothermal diffusion and growth of micron-scale liquid domains within membranes of free-floating giant unilamellar vesicles with diameters between 80 and 250 μm. Domains appear after a rapid temperature quench, when the membrane is cooled through a miscibility phase transition such that coexisting liquid phases form. In membranes quenched far from a miscibility critical point, circular domains nucleate and then progress within seconds to late stage coarsening in which domains grow via two mechanisms 1), collision and coalescence of liquid domains, and 2), Ostwald ripening. Both mechanisms are expected to yield the same growth exponent, α = 1/3, where domain radius grows as time(α). We measure α = 0.28 ± 0.05, in excellent agreement. In membranes close to a miscibility critical point, the two liquid phases in the membrane are bicontinuous. A quench near the critical composition results in rapid changes in morphology of elongated domains. In this case, we measure α = 0.50 ± 0.16, consistent with theory and simulation.
authors.affiliation: Department of Chemistry and Physics, University of Washington, Seattle, Washington, USA.
authors.forename: Cynthia A
authors.initials: CA
authors.lastname: Stanich
authors.forename: Aurelia R
authors.initials: AR
authors.lastname: Honerkamp-Smith
authors.forename: Gregory Garbès
authors.initials: GG
authors.lastname: Putzel
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Warth
authors.forename: Andrea K
authors.initials: AK
authors.lastname: Lamprecht
authors.forename: Pritam
authors.initials: P
authors.lastname: Mandal
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Mann
authors.forename: Thien-An D
authors.initials: TA
authors.lastname: Hua
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Keller
mesh_terms: D004058:Diffusion; D007700:Kinetics; D008055:Lipids / Q000737:chemistry; D013696:Temperature; D053835:Unilamellar Liposomes / Q000737:chemistry*
chemical_list: D008055:Lipids; D053835:Unilamellar Liposomes