Nanoemulsions as Vehicle for Topical 8-Methoxypsoralen Delivery

DipartimentoFarmacoChimicoTecnologico,UniversitadegliStudidiCagliari,ViaOspedale72,09124Cagliari,ItalyThis work describes preparation, characterization and properties of nanoemulsion formulations asdrug carrier systems for topical application of 8-methoxypsoralen (8-MOP). The lipid emulsionswere prepared from soy bean oil, as oil phase, different mixtures of phospholipids as emulsifiers(soy phosphatidylcholine or hydrogenated soy phosphatidylcholine or soy lecithin), and a mixturewater/glycerine as aqueous phase. To characterize the physicochemical properties of the lipidnanoemulsions, average diameter, polydispersity index and Zeta potential were determined. Theeffects of the nanoemulsion incorporation on the 8-MOP diffusion through and into the skin wereinvestigated in vitro using newborn pig skin. Data showed that 8-MOP was predominantly localizedin the different skin layers, with a minimal amount (less than 0.05% of the applied dose)detectedin the receptor compartment.