FORMULATION AND EVALUATION OF DRUG RELEASE FROM CHLORHEXIDINE FILMS

Abstract

This study dealt with the release rate of chlorhexidine acetate from the various prepared films into citrate buffer (PH=5.03). The results revealed that, the release of chlorhexidine from films composed of different ratios of ethylcellulose (EC) and hydrox-ypropyl methylcellulose (HPMC) was different. As the ratio of HPMC increased the rate of drug release increased. In addition, films Composed of EC:HPMC in a ratio of 8:2 was found to be the most proper film, since about 35% of the drug was released over 8 hours. Incorporation of different concentrations of plasticizers (10, 20 and 30% w/w of polymer) showed an increase in the drug release with increasing plasticizer concentration. The effect of different plasticizers used can be arranged according to their effect on the rate of drug release from medicated films in the following descending order: polyethylene glycol 400>glycerin>propylene glycol. Morever, incorporation of different concentrations of enhancers (1% soduim dodecyl sulphate, urea (10 and 20% ) and Tween 80 (5 and 10%) to the medicated selected films plasticzed with 20% propylene glycol enhanced drug release. Different concentrations of chlorhexidine acetate ( 3, 6, 9, 12 and 15% w/w of dry film) were tested. The results proved that the greatest drug release was observed from films containing 15% w/w of the drug. The effect of film thickness on the release rate was also tested using four different film thicknesses containing the same drug concentration. The results proved that, as the film thickness increased the percentage of drug release decreased. Finally, it was concluded that films composed of a mixture of EC and HPMC in a ratio of 8:2 plasticized with propylene glycol 20% and containing 10% Tween 80, produced about 85% chlorhexidine release after ten hours and was selected as the most suitable and proper formula for pharmaceutical applications.