title: Spontaneously formed unilamellar vesicles with path-dependent size distribution.
abstract: We observe the spontaneous formation of path-dependent monodisperse and polydisperse phospholipid unilamellar vesicles (ULV) from two different equilibrium morphologies specifically, disklike micelles and extended lamellae, respectively. On heating beyond a temperature Tc, low temperature disklike micelles, or so-called bicelles, transform into lamellae. Dilution of the lamellar phase, at a fixed temperature, results in a complete unbinding transition and the formation of polydisperse ULV, demonstrating the instability of the lamellar phase. On the other hand, heating of a dilute bicellar phase above Tc results in monodisperse ULV, which on cooling revert back to bicelles for lipid concentrations phi > or = 0.5 wt % and transform into oblate ellipsoids for phi = 0.1 wt %, a morphology not previously seen in "bicellar" lipid mixtures. Monodisperse ULV reform on heating of the oblate ellipsoids.
authors: National Research Council, Steacie Institute for Molecular Sciences, Chalk River, Ontario, K0J 1J0, Canada.
authors: Mu-Ping
authors: MP
authors: Nieh
authors: Velayudhan A
authors: VA
authors: Raghunathan
authors: Steve R
authors: SR
authors: Kline
authors: Thad A
authors: TA
authors: Harroun
authors: Chien-Yueh
authors: CY
authors: Huang
authors: Jeremy
authors: J
authors: Pencer
authors: John
authors: J
authors: Katsaras