Design and characterization of bioadhesive ophthalmic films of flurbiprofen

Abstract

An attempt has been made to formulate sustained release ophthalmic films of flurbiprofen along with bioadhesive polymers. Ocular films were prepared by using polymers; sodium alginate, chitosan and HPMC; alone and in different combinations. Glycerol was used as plasticizer. The films were prepared by solvent casting technique and were evaluated for thickness, weight variation, folding endurance, irritancy, drug content, mechanical strength, surface pH, swelling capacity, and bioadhesive strength. In vitro drug release studies were done using bio-donar receptor compartment model. In vitro drug release data was treated according to zero, first, Korsemeyer Peppas and Higuchi kinetics to access the mechanism of drug release. All the formulations followed zero-order release kinetics. Fickian diffusion was observed for the given formulations as the value of n lies almost equal to 0.5 for most of the formulations. The optimized formulation was subjected to in vivo studies using rabbits as an animal model. An ideal zero order kinetics was observed for in vivo drug release. Optimized formulation was tested and compared with eye drops of flurbiprofen for ocular anti-inflammatory activity in rabbits against PGE2-induced inflammation; parameters like polymorphonuclear leukocyte (PMN) migration and lid closure were observed. Films showed a significant anti-inflammatory activity in comparison to eye drops. Thus the prepared films achieved target of increased residence time, prolonged drug release, reduction in frequency of administration and may improve the patient compliance.