title: Preparation and characterization of a stratum corneum substitute for in vitro percutaneous penetration studies.
abstract: The intercellular stratum corneum (SC) lipids form the main barrier for diffusion of substances through the skin. A porous substrate covered with synthetic SC lipids would be an attractive model to study percutaneous penetration, hereby replacing native human SC. Prerequisite is that this stratum corneum substitute (SCS) is prepared with a uniform lipid composition and layer thickness. Furthermore, the lipid organization and orientation should resemble that in SC. The objective of this study was to investigate the utility of an airbrush spraying device to prepare a SCS composed of cholesterol, ceramides and free fatty acids on a polycarbonate filter. The results demonstrate that a proper choice of solvent mixture and lipid concentration is crucial to achieve a uniform distribution of the applied lipids over the filter surface. A smooth and tightly packed lipid layer is only obtained when the equilibration conditions are appropriately chosen. The SCS possesses two crystalline lamellar phases with periodicities similar to those present in native SC. The orientation of these lamellae is mainly parallel to the surface of the polycarbonate filter, which resembles the orientation of the intercellular SC lipids. In conclusion, the airbrush technique enables generation of a homogeneous SCS, which ultimately may function as a predictive in vitro percutaneous penetration model.
authors.affiliation: Leiden/Amsterdam Center for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
authors.forename: Miranda
authors.initials: M
authors.lastname: de Jager
authors.forename: Wouter
authors.initials: W
authors.lastname: Groenink
authors.forename: Joop
authors.initials: J
authors.lastname: van der Spek
authors.forename: Co
authors.initials: C
authors.lastname: Janmaat
authors.forename: Gert
authors.initials: G
authors.lastname: Gooris
authors.forename: Maria
authors.initials: M
authors.lastname: Ponec
authors.forename: Joke
authors.initials: J
authors.lastname: Bouwstra
mesh_terms: D002855:Chromatography, Thin Layer; D020285:Cryoelectron Microscopy; D004058:Diffusion; D066298:In Vitro Techniques; D008055:Lipids / Q000737:chemistry; D012869:Skin Absorption; D017768:Skin, Artificial; D014961:X-Ray Diffraction
chemical_list: D008055:Lipids