ABSTRACT
Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLC) are novel colloidal delivery systems with many cosmetic and dermatological features, such as adhesive properties when applied to the skin. Physical stability of the aqueous SLN and NLC dispersions, that is, the absence of particle aggregation and creaming, is a prerequisite for the formulation of cosmetic and pharmaceutical products based on SLNs and NLCs. In NLC formulations, lipid nanoparticles have a liquid core, and clotrimazole is incorporated in the oil less tightly in comparison to the solid lipid matrix of SLN formulations. The sheer forces and cavitation forces in the homogenizer are strong enough to break the microparticles directly into lipid nanoparticles. The solvent emulsification-evaporation is a method analogous to the production of polymeric nanoparticles and microparticles by solvent evaporation in o/w emulsions. The main feature of lipid nanoparticles intended for dermal and transdermal delivery of drugs is their controlled-release properties.
