Liposomes are microvesicles made out of a bilayer of lipid amphipathic molecules, encasing a fluid compartment. The principle constituent of liposomes is phospholipid which contains a hydrophobic tail and hydrophilic head groups which empowers the liposomes to sort out into round bilayer direction in watery media. The hydrophobic tail and hydrophilic head group of the phospholipids is the reason for entrapping both water dissolvable and lipid solvent substances, while staying scattered in the fluid condition. Besides its various points of interest the real restriction in the helpful utilization of customary liposomes upon intravenous organization lies in its quick disposal from the blood and acknowledgment by the reticuloendothelial system (RES). This prompts the improvement of surface changed sterically stabilized liposomes or the stealth liposomes. The nearness of polymers on the outside of liposomes has been appeared to enhance the blood flow time without being effectively perceived by the intrinsic insusceptible framework. This review centers around the development of stealth liposomes, summarizes the generally utilized polymers for the development and finally the applications of this promising innovation.

Keywords : PEG, Stealth Liposomes, Reticulo Endothelial System, Drug Delivery.