Formulation and evaluation of drug-free ophthalmic films prepared by using various synthetic polymers

An attempt has been made to formulate drug-free ophthalmic Þ lms by using different polymers in single use as well as in combinations for matrix system design for ocular use and to study the effect of various plasticizers on physicochemical characteristics and permeability of the resultant Þ lms. Drug-free Þ lms of hydroxypropyl methyl cellulose (HPMC), polyvinyl alcohol (PVA), hydroxypropyl cellulose (HPC), polyvinyl pyrrolidone (PVP), and Eudragit RL 100 polymers were prepared by the solvent casting method on a mercury surface by employing distilled water and ethanol as solvents, and glycerol and dibutyl phthalate as plasticizers. These Þ lms were evaluated for weight variation, uniformity of thickness, tensile strength, percentage of elongation at break, folding endurance, hardness, surface pH, and water vapor permeability. Permeability characteristics of these Þ lms were studied using Os oxacine as a model drug. Film properties of various synthetic polymers such as hydroxypropyl methyl cellulose (HPMC), polyvinyl alcohol (PVA), hydroxypropyl cellulose (HPC), polyvinyl pyrrolidone (PVP), and Eudragit RL 100 were studied for their utility in the formulation of ophthalmic inserts. Sterility test was carried out before performing an irritation study on albino rabbit eyes. There was no sign of any irritation, redness, swelling, or haziness in the rabbit’s eyes even after 24 hours after removal of the Þ lm. Key words: Eudragit RL 100, hydroxypropyl methyl cellulose, hydroxypropyl cellulose, ophthalmic inserts, polyvinyl alcohol, polyvinyl pyrrolidone.