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 fix...

The phase behavior of a melt of monodisperse rod-coil diblocks is studied. We derive a Landau free energy functional for both a compositional and a nematic order parameter. The excluded volume interaction between the rod blocks is modeled by an attractive Maier-Saupe interaction. The incompatibility between rodand coil blocks is modeled by the usual Flory-Huggins interaction. For large volume f...

forming lipids are removed and thus the constraints on formation of non-bilayer structures are reduced. The action of cryopreservatives, based on these effects of temperature and water activity on thc phase behaviour o f membrane lipids, may be predicted to affect membrane lipids in such a way as t o preserve the phase bchaviour close t o that prevailing at physiological temperatures. Thus cryo...

Novel gemini supra-amphiphiles, [Mim-4-Mim][DBS](2) and [Mim-4-Mim][DS](2), were facilely constructed. A slight variation of building blocks can effectively modulate the driving forces for the fabrication of gemini supra-amphiphiles, thus leading to the fine control of subsequent self-assemblies. [Mim-4-Mim][DS](2), constructed via electrostatic attraction, tends to form micelles and hexagonal ...

The development of plastid membranes was studied in relation to chlorophyll accumulation in dark-grown barley seedlings of various ages after transfer to light. Quantitative electron microscopy showed that the prolamellar body membranes are reorganized into primary lamellar layers which contain sufficient membranes to support grana formation during 24 h of greening. Structural reorganization of...

Caillé analysis of the small-angle X-ray line shape of the lamellar phase of 7:3 wt/wt cetyltrimethylammonium tosylate (CTAT)/sodium dodecylbenzene sulfonate (SDBS) bilayers shows that the bending elastic constant is kappa = (0.62 +/- 0.09)k(B)T. From this and previous results, the Gaussian curvature constant is kappa = (-0.9 +/- 0.2)k(B)T. For 13:7 wt/wt CTAT/SDBS bilayers, the measured bendin...

We investigate the ability of Monte-Carlo algorithms to describe the single-chain dynamics in a dense homogeneous melt and a lamellar phase of a symmetric diblock copolymer. A minimal, coarse-grained model is employed that describes connectivity of effective segments by harmonic springs and where segments interact via soft potentials, which do not enforce noncrossability of the chain molecules....

Lipid lamellae present in the outermost layer of the skin, the stratum corneum, form the main barrier for the diffusion of molecules through the skin. The presence of a unique 13 nm lamellar phase and its high crystallinity are characteristic for the stratum corneum lipid phase behavior. In the present study, small-angle and wide-angle X-ray diffraction were used to examine the organization in ...

Complex multi-lamellar structures play a critical role in biological systems, where they are present as lamellar bodies, and as part of biological assemblies that control energy transduction processes. Multi-lamellar lipid layers not only provide interesting systems for fundamental research on membrane structure and bilayer-associated polypeptides, but can also serve as components in bioinspire...