Niosomes: a novel approach in modern drug delivery systems

Niosomes as a novel drug delivery system is a nonionic surfactant-based vesicle.The twofold structure of surfactant molecules encourages them to orient in bilayer architecture. In this two-layered structure, hydrophilic and hydrophobic ends of surfactant tend to arrange into external and internal sites, respectively. This lamellar morphology allows us to entrap two kinds of drugs in a unique carrier simultaneously. Several factors affect the structure of niosomes, such as: the nature and type of surfactants, amount of cholesterol, the critical packing parameter (CPP), and the used drug. These systems can be designed in a way that is prescribed via different administration routes, such as oral, parenteral, topical, and so forth for use in drug delivery. It is a fact that liposomes are similar to the niosomes in structure, but niosomes are more stable and also more cost-effective than liposomes. Niosomes remain in the bloodstream for a reasonable time, which is useful for targeted drug delivery. In this chapter, we attempt to introduce these new drug delivery vehicles and give a brief description on the preparation, applications, and advantages and disadvantages of this system.