title: A unique bicellar nanosystem combining two effects on stratum corneum lipids.
abstract: In this work a new composition (dioleylphosphatidylcholine, DOPC, and dihexanoylphosphocholine, DHPC) is used to form the bicellar system and to evaluate their effect on stratum corneum (SC) lipids. Through this article, "bicellar system" will refer to a lipid binary system in which lipids are self-assembled forming different nanostructures. DOPC/DHPC system is characterized by dynamic light scattering and cryo-transmission electron microscopy showing two different nanostructures: unilamellar vesicles and tubular structures. In order to study the SC lipid organization attenuated total reflectance Fourier transform infrared spectroscopy, freeze-substitution applied to transmission electron microscopy and X-ray scattering are used. This work compares for the first time the use of two different X-ray scattering methods, transmission with synchrotron radiation and grazing incidence with conventional source, for skin studies. Our results indicate that vesicle-shaped structures remain adhered to the SC surface being unable to penetrate into the skin probably due to their large and voluminous size, while a proportion of structures could have interaction with SC lipids increasing the lamellar organization. Thus, the different nanostructures present in the system have different effects on SC lipids. The appropriate combination of both effects and the possibility to incorporate drugs offer a range of possibilities for the DOPC/DHPC system in development for skin care products.
authors.affiliation: Department of Chemical and Surfactants Technology, Institute of Advanced Chemistry of Catalonia, IQAC-CSIC, 08034 Barcelona, Spain. gelen.rodriguez@cid.csic.es
authors.forename: Gelen
authors.initials: G
authors.lastname: Rodríguez
authors.forename: Mercedes
authors.initials: M
authors.lastname: Cócera
authors.forename: Laia
authors.initials: L
authors.lastname: Rubio
authors.forename: Carmen
authors.initials: C
authors.lastname: López-Iglesias
authors.forename: Ramon
authors.initials: R
authors.lastname: Pons
authors.forename: Alfons
authors.initials: A
authors.lastname: de la Maza
authors.forename: Olga
authors.initials: O
authors.lastname: López
mesh_terms: D000818:Animals; D020285:Cryoelectron Microscopy; D004817:Epidermis / Q000737:chemistry* / Q000187:drug effects; D008055:Lipids / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010713:Phosphatidylcholines / Q000737:chemistry; D010743:Phospholipids / Q000737:chemistry; D012867:Skin / Q000737:chemistry* / Q000187:drug effects / Q000648:ultrastructure; D017550:Spectroscopy, Fourier Transform Infrared; D013552:Swine
chemical_list: D008055:Lipids; D010713:Phosphatidylcholines; D010743:Phospholipids; C032166:1,2-hexanoylphosphatidylcholine; C017251:1,2-oleoylphosphatidylcholine