A PHASE OF LIPOSOMES WITH ENTANGLED TUBULAR VESICLES

An equilibrium phase belonging to the family of bilayer liposomes in t ernary mixtures of dimyristoylphosphatidylcholine (DMPC), water, and g eraniol (a biological alcohol derived from oil-soluble vitamins that a cts as a cosurfactant) has been identified. Electron and optical micro scopy reveal the phase, labeled L(tv), to be composed of highly entang led tubular vesicles. In situ x-ray diffraction confirms that the tubu le walls are multilamellar with the lipids in the chain-melted state. Macroscopic observations show that the L(tv) phase coexists with the w ell-known L(4) phase of spherical vesicles and a bulk L(alpha) phase. However, the defining characteristic oi the L(tv) phase is the Weissen berg rod climbing effect under shear, which results from its polymer-l ike entangled microstructure.