Cosmetic applications for solid lipid nanoparticles (SLN)

Solid lipid nanoparticles (SLN) are novel delivery systems for pharmaceutical and cosmetic active ingredients. This paper highlights advantages of SLN for cosmetic applications. The dependence of the occlusive effect on the particle size of SLN due to film formation is presented by in vitro data. An in vivo study showed that addition of 4% SLN to a conventional o/w cream lead to an increase of skin hydration of 31% after 4 weeks. The application of SLN as physical sunscreens and as active carriers for molecular sunscreens has also been investigated. The amount of molecular sunscreen could be decreased by 50% while maintaining the protection level compared to a conventional emulsion. (C) 2002 Elsevier Science B.V. All rights reserved.