Preparation and Characterization of Solid Lipid Nanoparticles-Based Gel for Topical Delivery.

Solid lipid nanoparticles (SLNs) have been extensively investigated for effective delivery of both hydrophilic and lipophilic drugs by topical route. There are several scalable techniques for the preparation of SLNs such as homogenization, microemulsion template, and solvent emulsification diffusion. This chapter describes step-wise methodology for the preparation and characterization of SLNs using solvent emulsification diffusion method. Tretinoin, a lipophilic entity, was chosen as a model drug. The critical aspects and the important interpretations with respect to the preparation and characterization of SLNs are reported in "Notes" section.