ABSTRACT

The objective of this study is to investigate physical characteristics of monolithic films and in vitro release of sotalol, prepared by either Eudragit E100 (E100) or Eudragit RL100 (RL100) combined in a ratio of 50 % w/w with Eudragit NE40D (NE40D). Films including 3 % w/w sotalol of dry polymer weight were prepared from methanol: acetone solvent mixture moulded onto a PVA backing membrane. The pore former effect of adipic acid or citric acid monohydrate (1.5 % w/w and 5% w/w) was evaluated on the E100:NE40D film in order to modify the release of sotalol. Uniformity offilms was evidenced by low standard deviations of thickness and drug amount studies as well as high sotalol contents. The in vitro release studies carried out by vertical Franz cells. Films formulated with RL100 polymer gave higher degrees of swelling accompanied with higher in vitr o release rates of drug that could attributed to the higher permeability of this polymer. The existence of organic acids inside of films affected the release profiles and acid pKa value with low aqueous solubility of adipic acid caused a rapid release of drug rather than citric acid. Morphological analysis of acid containing films performed by scanning electron microscopy supported the drug release data. Obtained kinetic data from in vitro dissolution profiles indicated that drug release governed by diffusion mechanism.