About Author: DEVANG V. PATEL*, Manju Misra
M.S.(PHARM.) PHARMACEUTICS
NATIONAL INSTITUTE OF PHARMACEUTICAL EDUCATION & RESEARCH (NIPER), AHMEDABAD.
Abstract
Drug targeting is the ability to direct a therapeutic agent specifically to desired site of action with little or no interaction with nontarget tissue. Niosomes are one of the best carriers for drug targeting. Niosomes (non-ionic surfactant vesicles) are microscopic lamellar structures formed on admixture of non-ionic surfactant of the alkyl or dialkyl polyglycerol ether class and cholesterol with subsequent hydration in aqueous media. Niosomes are biodegradable, relatively nontoxic, more stable and inexpensive, an alternative to liposomes. Niosomes can be SUV (Small Unilamellar Vesicles), MLV (Multilamellr Vesicles) or LUV (Large Unilamellar Vesicles). The method of preparation of niosome is the based on liposome technology. The basic process of preparation is the same i.e. hydration of the lipid phase by aqueous phase. After preparing niosomal dispersion, unentrapped drug is separated by dialysis, centrifugation or gel filtration. Niosomes are characterized by vesicle size, bilayer formation, number of lamellae, membrane rigidity and entrapment efficiency. A method of in-vitro release rate study includes the use of dialysis tubing. Niosomal drug delivery is potentially applicable to many pharmacological agents for their action against various diseases including cancer and leishmaniasis.