Formulation development, in vitro and in vivo evaluation of membrane controlled transdermal systems of glibenclamide

The objective of the present study was to develop the membrane controlled transdermal systems of glibenclamide and to evaluate with respect o various in vitro and in vivo parameters.

The membrane moderated transdermal systems were prepared using drug containing carbopol gel as reservoir and ethyl cellulose, Eudragit RS-100, Eudragit RL-100 and Ethylene vinyl acetate (EVA) (2%, 9% and 19% vinyl acetate content) rate controlling membranes. The possible interaction between drug and polymer was studied by IR spectroscopy, DSC and HPTLC analysis. The formulations were subjected to various physicochemical studies, in vitro drug release studies and permeation studies through mouse skin. The blood glucose reducing hypoglycemic activity of the systems was studied in both normal and diabetic mice. Various biochemical parameters and histopathological studies were carried out after treating the diabetic mice for 6 weeks. Skin irritation tests, oral glucose tolerance test and pharmacokinetic evaluations were carried out in mice.

The results suggested no interaction between drug and polymer. Variations in drug release/permeation profiles among the formulations containing different rate controlling membranes were observed. The scanning electron microscopic studies of EVA membranes demonstrated no changes in the surface morphology after in vitro skin permeation studies. The system with EVA rate controlling membrane (with 19% vinyl acetate) was selected for in vivo experiments. The transdermal system produced better improvement with respect to hypoglycemic activity, glucose tolerance test, all the tested biochemical, histopathological and pharmacokinetic parameters compared to oral administration, and exhibited negligible skin irritation.

The present study shows that membrane controlled transdermal systems of glibenclamide exhibited better control of hyperglycemia and more effectively reversed the diabetes mellitus complications than oral glibenclamide administration in mice.