Comparison of vegetable and volatile oils as skin permeation enhancers for transdermal delivery of losartan potassium

The present work comprises the formulation and evaluation delivery system of transdermal drug with a view of developing and preparing a losartan potassium releasing system utilizing natural oils as permeation enhancers for transdermal applications. Matrix systems were prepared by using polyvinyl pyrrolidine and ethyl cellulose (EC) polymers by incorporating dibutyl phthalate as plasticizer and chloroform as solvent. The physicochemical and in vitro drug release studies indicated that formulation containing PVP and EC in the ratio of 3:2 was better than other combination of polymers.Penetration enhancing potential of vegetable oils (jojoba oil, sunflower oil, sesame oil) and volatile oils (clove oil, peppermint oil, eucalyptus oil) was determined by incorporating oils in different concentration in optimized transdermal patch and in vitro permeation of losartan potassium across goat skin was studied. Maximum transdermal flux of 0.29 mg/cm/h was obtained with formulation containing 10 % jojoba oil (vegetable oil) as permeation enhancer while in case of volatile oil maximum transdermal flux of 0.27 mg/cm/h was obtained with 10% peppermint oil as permeation enhancer respectively. The results of permeation fluxes supported the data for prolongation of drug release characteristics of formulated transdermal films. The release kinetics revealed that the release was sustained and it follows zero-order kinetics. Stability studies of optimized formulation were stable at 45° C &75% RH with respect to their physical parameters and in vitro drug release. This suggests the transdermal application of losartan potassium holds promising for improved bioavailability and better alternative to oral dosage form in hypertensive patients.