Application of Neutron Diffraction for Localization of Specifically Deuterated Penetration Enhancers in Oriented Stratum Corneum Model Membranes

The unique lamellar lipid matrix of the stratum corneum (SC) is known to play a key role in forming the main protecting barrier of the mammalian skin. This barrier function can be influenced e.g. by application of penetration enhancers. To learn more about their mode of action, the present study aimed at the characterization of the influence of lipophilic penetration enhancers like oleic acid (OA) on the bilayer structure of highly oriented SC model membranes. For exact localization of the enhancer molecules inside the bilayers of the studied quaternary SC models, we applied specifically deuterated penetration enhancers (e.g. OA-9,10-D2 and isopropyl myristate-14,14,14,13,13-D5) to the samples which were investigated by means of neutron diffraction. Benefitting from the advantages offered by the neutron diffraction technique, we could evaluate the exact position of the deuterium labels inside the membrane. Furthermore, hydration properties of the membrane could be studied and the bilayer architecture was elucidated by calculating the neutron scattering length density (neutron SLD) profiles using Fourier transform.View Large Image | View Hi-Res Image | Download PowerPoint Slide