Preparation of a transdermal delivery system and effect of membrane type for scopolamine drug

The aim of this study was to clarify the performance of a membrane controlled reservoir system (MCRS) for scopolamine hydrobromide (SH) under in vitro condition by determination of the role of membrane on SH rate control. In this method SH was incorporated into two polymers (polyisobutylene and polybutyl acrylate) and SH rate across ethylene-vinyl acetate copolymer (EVA) and ethyl cellulose (EC) membranes were measured. The results obtained showed that in the EVA membrane, the permeability of SH across membrane increased with the increase of vinyl acetate percentage in copolymer. Microscopic studies of EVA membrane surface showed that the size of surface porosity increases with the increase of vinyl acetate percentage in the copolymer and according to the results obtained, it showed an increase in drug's release rate. In the case of EC membrane, the results showed that the rate of release increases with the increase of porosity size of EC surface despite of having high molecular weight.