Fig. 3
From: Nanomedicine review: clinical developments in liposomal applications
a Chemical structure of hydrogenated soybean phosphatidylcholine (HSPC), a phospholipid used in Doxil®, the first approved liposomal nanoformulation. Brackets indicate the polar and non-polar portions of the phospholipid. b Scheme of the membrane permeability of liposomes with unsaturated phospholipids. Blue figures represent charged compounds while orange ones have no charge: the circles represent the polar head of phospholipids; bars, the fatty acid chains; hexagons, hydrophobic drugs; and triangles, the hydrophilic drugs (schematic image done with Adobe® Photoshop® CS6)