Rheological characterization of thermal phase behavior of anionic lipid DMPG dispersions

Abstract

We study thermo-structural behavior of anionic lipid 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) dispersed systems. Continuous chain-melting transition of DMPG induces anomalous intermediate phase between gel and fluid phases. We found that the intermediate phase can be divided into two domains; anisotropic phase with high orientational order and isotropic viscous phase. Anisotropic phase would be identified to perforated lamellae or bicelle formed by rupturing the perforated vesicles under shear. Isotropic viscous phase, on the other hand, might be identified to densely packed perforated vesicle dispersions formed by rearranging extended bilayer membranes.