[SCAN] Organized lipids - More predictable than we imagine, more deceiving than we would like

Scan Seminar

Title: Organized lipids - More predictable than we imagine, more deceiving than we would like

Speaker: Eurico Melo

From: Microheterogeneous Systems Lab, ITQB

Abstract:
The thermal area expansion coefficient of lipid bilayers is an important parameter not easy to determine experimentally. We developed a direct and expedite method for its determination using dynamic light scattering of unilamellar vesicles. As predictable, they expand like normal hydrocarbons. However, X-ray powder diffraction of multilamellar vesicles shows a much different scenario only understandable if the well established dogma of ready permeation of bilayers to water is defied.

Lipids in the skin stratum corneum organize in weird multilamellar structures that have been explained using speculative models some of them credible but never confirmed. Since decades extracts of skin lipids deceive the researchers by seeming to adopt the same structure found in the stratum corneum. I will show that it is an artifact, and tell what the predictable but unconfirmed answer is.