FORMULATION DEVELOPMENT & EVALUATION OF IN SITU GEL

Poor bioavailability of drugs from conventional eye drops is mainly due to the various precorneal loss factors which include rapid tear turnover, systemic drug absorption through naso-lachrymal duct, and transient residence time of the drug solution in the cul-de-sac and the relative impermeability of the drugs to corneal epithelial membrane. In situ gels are systems which are applied as solutions or suspensions and are capable of undergoing rapid sol-to-gel transformation triggered by external stimulus such as temperature, pH etc on instillation. The purpose of the present research work was to develop and evaluation sustains release in situ ophthalmic gel of dexamethasone and levofloxacin. The different gelling solutions were made with Pluronic F127 in combination with different polymers such as Carbopol 934 and HPMC, which acted as a viscosity-enhancing agent. Suitable concentrations of buffering agent were used for pH adjustment. All the formulations were sterilized in an autoclave at 121°C for 15 minutes. The formulations were evaluated for clarity, pH measurement, gelling capacity, drug content, rheological study, sterility testing, in vitro study, ocular irritation study.