Influence of Soapnut Powder on the Permeability of Eudragit RL100 Free Films for Transdermal Use

The influence of Soapnut on the permeability of Eudragit RL100 films was studied with a view to develop a suitable rate controlling membranes for transdermal use. Dibutyl phthalate was incorporated at a concentration of 15% w/w of dry polymer as plasticizer. The dry free films were evaluated for various mechanical properties further the permeability characteristics of free films was studied using propranalol hydrochloride and diltiazem hydrochloride as model drugs. Both water vapour transmission and drug diffusion rate followed zero order kinetics. The soapnut powder showed a significant influence on the mechanical as well as permeability characteristics. This may be due to difference in the affinity of soapnut with the film former. From this study it was concluded that the plasticized free films of Eudragit RL100 prepared with soapnut can be used as rate controlling membranes to develop transdermal drug delivery systems.