Niosomes

During the past decades the use of vesicles for drug delivery has been established. One of these vesicular systems is the niosomes; these may be unilamellar or multilamellar. The niosome bilayer is different from the liposome bilayer in that niosomes are prepared from uncharged single-chain surfactants with the incorporation of cholesterol or other amphiphilic molecules, whereas liposomes are prepared from double-chain phospholipids (neutral or charged) and cholesterol. As with liposomes, the in vitro/in vivo properties of niosomes depend both on the composition of the bilayer and on method of their production. Niosomes may be used as carriers of both hydrophilic and lipophilic drugs. In this chapter, niosome formation, composition, preparation, characterization, evaluation, advantages, disadvantages, and the more recent applications of niosomes are extensively discussed.