Chiruvolu, Shivkumar; Warriner, Heidi E.; Naranjo, Edward; Idziak, Stefan H. J.; Rädler, Joachim O.; Plano, Robert J.; Zasadzinski, Joseph A.; Safinya, Cyrus R.
(18. November 1994):
A phase of liposomes with entangled tubular vesicles.
In: Science, Vol. 266, No. 5188: pp. 1222-1224
An equilibrium phase belonging to the family of bilayer liposomes in ternary mixtures of dimyristoylphosphatidylcholine (DMPC), water, and geraniol (a biological alcohol derived from oil-soluble vitamins that acts as a cosurfactant) has been identified. Electron and optical microscopy reveal the phase, labeled Ltv, to be composed of highly entangled tubular vesicles. In situ x-ray diffraction confirms that the tubule walls are multilamellar with the lipids in the chain-melted state. Macroscopic observations show that the Ltv phase coexists with the well-known L4 phase of spherical vesicles and a bulk L alpha phase. However, the defining characteristic of the Ltv phase is the Weissenberg rod climbing effect under shear, which results from its polymer-like entangled microstructure.