Solid lipid nanoparticles (SLNs), Stability, Administration routes, Controlled release, Colloidal drug carrier.

SLN’s are colloidal carriers developed in the 1990s as an alternative system to the existing traditional carriers (emulsions, liposomes, and polymeric nanoparticles)1. Nanoparticles made from solid lipids are attracting major attention as novel colloidal drug carrier for various applications as they have been proposed as an alternative particulate carrier system. The SLNS are submicron colloidal carriers (50-1000 nm) which are composed of physiological lipid, dispersed in water or in an aqueous surfactant solution2.SLNs are particles consisting of a matrix made from solid lipids. In aqueous dispersion they are stabilised by surfactants or polymers. They consist of a solid matrix protecting incorporated active substances against chemical degradation and providing high flexibility to modify release profiles. The SLN combine the advantages (e.g. physical stability, protection of incorporated labile drugs from degradation, controlled release, excellent tolerability, and scalability to large-scale preparations, excellent biocompatibility) of other traditional colloidal systems3.