DEVELOPMENT OF PHASE CHANGE SOLUTIONS FOR OPHTHALMIC DRUG DELIVERY BASED ON ION ACTIVATED AND PH INDUCED POLYMERS

Abstract

The optimal drug concentration required at the site of action for the ocular treatment cannot be attained mainly due to precorneal drug loss; tear turn over, solution drainage by gravity and naso-lachrymal drainage. The purpose of present work was to overcome these problems by developing an in situ gel forming systems of flurbiprofen, based on the ion-activated and pH-induced in situ gelation. In situ gels of flurbiprofen were prepared by simple dispersion method using sodium alginate and carbopol along with HPMC and then evaluated for pH, gelling capacity, rheological, isotonicity, in vitro and in vivo studies. The above mentioned evaluation showed satisfactory results in formulation L4(2% alginate and 0.4% HPMC) as it showed better gelation, acceptable pH, prolonged in vitro drug release and was found isotonic. In vivo studies with L4 indicated a noteworthy resistance of PGE2-prevailed lid closure and PMN migration as compared to flurbiprofen eye drops indicating a better & higher pharmacodynamic effect of in situ gel as compared to eye drop. Formulation L4 showed promising results, as it increased the precorneal residence time of the drug and intensified the ocular bioavailability of flurbiprofen as compared to flurbiprofen eye drops.