Nonionic surfactant vesicles as a carrier for transdermal delivery of frusemide

The aim of the present study was to formulate and evaluate the nonionic surfactant vesicles of frusemide in order to enhance its skin permeation. The process variables which could affect the preparation and properties of the niosome formulation studied included type of spans, ratio of span and cholesterol, ratio of cholesterol and dicetylphosphate (DCP), concentration of drug, type of solvent, hydration media and time of hydration. The formulated niosomes thus were characterized for various parameters such as surface morphology, size, entrapment efficiency, skin permeation, etc. Stability of the niosomes in terms of drug holding capacity was assessed for a period of 30 days on storage under defined conditions. The maximum entrapment efficiency of 77.73 +/- 2.36% was obtained with niosomes formulated from Span 60:Cholesterol:DCP (47.5:47.5:5) using chloroform:methanol (4:1) as the solvent system at the hydration time of 1hr. A direct relationship was observed between the percentage leaching of the drug out of the vesicles and temperature. Higher transdermal flux was obtained with niosomal gel (9.2 +/- 0.5 mu g/cm(2)/hour) in comparison to conventional gel (6.4 +/- 0.3 mu g/cm(2)/hour).