ETHOSOMES: A NOVEL APPROACH IN TRANSDERMAL DELIVERY OF THE DRUGS

Abstract

Skin acts as a major target as well as a principal barrier for topical/transdermal drug delivery. Despite the many advantages of this system, the major obstacle is the low diffusion rate of drugs across the stratum corneum. Several methods have been tried to increase the permeation rate of drugs temporarily. One simple and convenient approach is application of drugs in formulation with elastic vesicles or skin enhancers. Vesicular system is one of the most convenient methods for transdermal delivery of active substances and in that ethosomes are most useful vesicular systems. Ethosomal carriers are systems containing soft vesicles, composed of hydroalcoholic or hydro/glycolic phospholipid in which the concentration of alcohols is relatively high. The high concentration of ethanol brings increase in fluidity of lipids hence increase in permeability of the skin and improves the drug penetration. Ethosomal formulation may contain many drugs such as acyclovir, salbutamol, Insulin, cyclosporine, fluconazole, minodixil, etc. These are prepared by hot method and cold methods. The size of Ethosomal formulation can be decreased by sonication and extrusion method. The high concentration of ethanol makes the ethosomes unique and useful for transcellular delivery, delivery of hormones, anti-arthritis, anti-HIV etc.

 Thus, it can be a logical conclusion that ethosomal formulation possesses promising future in effective dermal/transdermal delivery of bioactive agents.

KEY WORDS: Stratum Corneum (SC), Liposome, Classic Liposomes, Ethosomes, Ethanol, Phospholipid, Vesicles, Transdermal Drug Delivery.