Mesh structures, surfactants

These phenomena have been explored elsewhere. Immense variability is allowed, and this depends on the particular surfactant or surfactant mix. So the question whether single-walled vesicles are thermodynamically stable or not depends on the lipid or lipid mix. Their existence does not necessarily require us to invoke non-equilibrium thermodynamics in biology. Some vesicles are stable, some are not, and this variability is exploited by nature. When the bilayer contains defects e.g. mesh structures (section 4.5)), the allowed structures are evidently more variable. 

Quaternary structure is akin to the mesostructure of lipid or surfactant self-assemblies, such as the aggregates characteristic of mesh-structures in bacterial protein coats (described in Chapter 4), or the cholesteric liquid crystals found in... 

AFM is particularly sensitive to the lateral structure in the film, and this has yielded some surprising results, showing that adsorbed surfactant layers contain aggregates that are strikingly similar to elements of complex fluid phases including spherical or globular and cylindrical micelles, branched or mesh structures, as well as (occasionally) conventional bilayers. ... 

Layered tin sulfide mesostructures were synthesized using a cationic surfactant as template, and tin chloride and sodium sulfide as sources of tin and sulfide [36], The structure was composed of Sn2S64 dimers charge-balanced by dodecylammonium cations. A mesostructured tin sulfide mesh phase was synthesized by reacting SnCl4, (NH4)2S and hexadecylamine (HDA) under aqueous basic conditions at 150°C [37], The structure was found to be... 

An intermediate phase of tetragonal syiiunetry - the T phase - has also been detected in a number of systems. A rod structure related to a square mesh surface was foimd to agree well with X-ray and NMR data on a perfluorinated surfactant-water mixture forming the T phase [22], [34]. These examples demonstrate that surfactant or lipid monolayers lining mesh surfaces as well and bilayers wrapped onto three-periodic minimal surfaces (IPMS) are indeed found in these self-assembled systems. 

FIG. 2.7 Relevant length scales for the colloidal structure of worm-like micelles contour length, Lc, entanglement length, /e, mesh size, m, persistence length, Zp and cross-sectional radius, rcs. Values shown are those measured for a solution with 1.5% total surfactant at a cetyltrimethylammonium tosylate (CTAT)/sodium dodecylbenzenesulfonate (SDBS) ratio of 97/3 with 0.10% added sodium tosylate. (Reproduced from Schubert, B.A., Kaler, E.W., and Wagner, N.J., Langmuir, 19, 4079 -089, 2003. With permission.)... 

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