Polymer-mediated interactions of fluid membranes in a lyotropic lamellar phase: a small angle X-ray and neutron scattering study

Abstract

Small angle X-ray and neutron scattering data on an effective three-component lamellar phase composed of water, a non adsorbing water-soluble polymer (polyvynilpyrolidone), fluid membranes, made from a mixture of a cationic surfactant (cetylpiridiumchloride) and a cosurfactant (hexanol), are presented for various membrane as well as polymer concentrations. The data are fitted with a recently proposed model which takes into account the geometry and the fluctuations of these periodic structures. This allows a quantitative study of the polymer contribution to the smectic compression modulusB of the lamellar phase. Four different regimes of polymer confinement are expected. The associated variations inB are compared to a recent theoretical model, which predicts the polymer-mediated contribution to the smectic compression modulus.

Elastic properties of polymer-doped dilute lamellar phases: A small-angle neutron scattering study

“…Recently, several experimental studies have shown that electrostatically stabilized lamellar phases are able to incorporate a large amount of water-soluble neutral polymers [1][2][3]. The properties of these polymer-doped lamellar phases begin to be investigated.…”

Fluctuation pressure of biomembranes in planar confinement

“…From an application point of view, lamellar phases of lipid bilayers have been used, for example, to measure the effect of additives, such as proteins or polymers, on the interaction between membranes [13][14][15]; the interpretation of these results depends strongly on the distance dependence of the fluctuation pressure. Therefore, a profound understanding of lamellar membrane stacks is very important both from a theoretical and an experimental point of view.…”

Shear-induced Onion Formation of Triblock Copolymer-embedded Surfactant Lamellar Phase

“…Negative contribution of the polymer on the compression modulus B has been reported both for the theoretically and experimentally. 15,16) Lamellar phase is generally stabilized with constant layer distance due to inter-membrane repulsive force. 17) In the presence of the polymer chain dissolved in the water layer, however, the constant layer distance is disturbed in this study, is increased, hydrophobic chain is compressed in the bilayer, and membrane thickness will be inhomogeneous due to the configuration entropy of polymer chain.…”