ABSTRACT
This chapter discusses the general features of Nanosized drug delivery systems with respect to manufacturing and performance. Solid lipids have been mainly used for rectal and dermal applications. Solvent emulsification/evaporation processes adapt techniques which have been previously used for the production of polymeric micro- and nanoparticles. Nanoparticles were only produced with solvents which distribute very rapidly into the aqueous phase, while larger particle sizes were obtained with more lipophilic solvents. Solid lipid nanodispersions (SLN) preparation techniques which are based on the dilution of microemulsions have been developed by M. R. Gasco and coworkers. Proposed advantages of SLN, compared with nanoemulsions, include increased protection capacity against drug degradation and controlled release possibilities due to the solid lipid matrix. Drug release from SLN and hybrid lipid particles could be controlled by either the diffusion of the drug or the erosion of the matrix.
