Tabriz University of Medical Sciences Advanced Pharmaceutical Bulletin 2228-5881 5 3 2015 09 19 Solid Lipid Nanoparticles and Nanostructured Lipid Carriers: Structure, Preparation and Application 305 313 10.15171/apb.2015.043 EN Neda Naseri Hadi Valizadeh Parvin Zakeri-Milani REVIEW 10.15171/apb.2015.043 2015 05 15 Lipid nanoparticles (LNPs) have attracted special interest during last few decades. Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) are two major types of Lipid-based nanoparticles. SLNs were developed to overcome the limitations of other colloidal carriers, such as emulsions, liposomes and polymeric nanoparticles because they have advantages like good release profile and targeted drug delivery with excellent physical stability. In the next generation of the lipid nanoparticle, NLCs are modified SLNs which improve the stability and capacity loading. Three structural models of NLCs have been proposed. These LNPs have potential applications in drug delivery field, research, cosmetics, clinical medicine, etc. This article focuses on features, structure and innovation of LNPs and presents a wide discussion about preparation methods, advantages, disadvantages and applications of LNPs by focusing on SLNs and NLCs.