Structure of solid lipid nanoparticles (SLNs). Structure of solid lipid nanoparticles (SLNs). SLNs are submicron particles that range between 50 and 100 nm in size, which are prepared from lipids that remain solid at room temperature and body temperature. The solid lipid is used as a matrix material in which hydrophobic drugs can be stored. The lipid matrix is then stabilized by biocompatible surfactants, which in this case, are phospholipid and/or lipid-PEG. Phatsapong Yingchoncharoen et al. Pharmacol Rev 2016;68:701-787 Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics