Ofloxacin Ocular Inserts: Design, Formulation and Evaluation

In developing a drug delivery strategy, issues of absorption, distribution, metabolism, and elimination must be considered. The eye presents unique opportunities and challenges when it comes to the delivery of pharmaceuticals. While absorption by this route is bungling, there are few side effects with conventional ocular dosage forms. Hence, ocular inserts were prepared with prolonged release of drug and minimum swelling within cul-de-sac using ofloxacin as a model drug; Hydroxy propyl methyl cellulose, Methyl cellulose, Poly vinyl pyrrolidone and Poly vinyl alcohol as polymers. PEG-400 was incorporated as plasticizer. The main purpose of the study is to deliver the drug in zero order kinetics. Methods: Solvent casting technique was followed to prepare ofloxacin ocular films. Eight formulations were formulated and subjected to various physicochemical evaluations. Ocular inserts prepared were smooth and passed all the evaluation tests performed. Formulation OF2 shows a maximum cumulative percentage drug release of 91.27 % at the end of 24 hours. Ocuserts formulated also passed the test for sterility. They showed zero-order release of the drug in the in vitro and in vivo release studies. The drug in the films was found to be active against selected microorganisms as was proved by microbial efficacy studies. A high correlation coefficient was found between in vitro and in vivo release rate studies. Shelf-life of the product was found to be more than one year. The results of in vitro, in vivo, kinetic treatment (zero order and Korsemeyer's regression values) and rate constant 'k' value suggest that OF2 was the best formulation among the formulations studied for formulating ofloxacin ocular insert.