title: Liposomogenic UV Absorbers are Water-Resistant on Pig Skin-A Model Study With Relevance for Sunscreens.
abstract: An important property of sunscreens is their water resistance after the application on human skin. In this work, the hypothesis that UV absorber molecules which are able to form liposomes, so-called liposomogenic UV absorbers, show better water resistance on a pig skin model than UV-absorbing molecules lacking this ability was tested. The assumption behind is that molecules which can form liposomes are able to integrate into the stratum corneum lipids of the skin. Three different liposomogenic UV absorbers were synthesized and their behavior investigated, leading to the confirmation of the hypothesis. With one of the liposomogenic UV absorbers, it was possible to show the integration of the UV absorber molecules into the bilayers of another liposome consisting of phosphatidylcholine, supporting the assumption that liposomogenic UV absorbers exhibit improved water resistance because they integrate into the skin lipids.
authors.affiliation: Global Development UV Protection & Scientific Liaisons, BASF Grenzach GmbH, Grenzach-Wyhlen, Germany. Electronic address: bernd.herzog@basf.com.
authors.forename: Bernd
authors.initials: B
authors.lastname: Herzog
authors.affiliation: Performance Materials Research, BASF Schweiz AG, Basel, Switzerland.
authors.forename: Dietmar
authors.initials: D
authors.lastname: Hüglin
authors.affiliation: R&D Alliances, Grenzach-Wyhlen, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Luther
mesh_terms: D000818:Animals; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D008081:Liposomes / Q000737:chemistry* / Q000378:metabolism; D010713:Phosphatidylcholines / Q000737:chemistry* / Q000378:metabolism; D012867:Skin / Q000378:metabolism; D012869:Skin Absorption; D013473:Sunscreening Agents / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D013552:Swine; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry* / Q000378:metabolism
chemical_list: D008051:Lipid Bilayers; D008081:Liposomes; D010713:Phosphatidylcholines; D013473:Sunscreening Agents; D014867:Water
keywords: UV/vis spectroscopy; adsorption; kinetics; light-scattering; liposomes; phospholipids; skin