Ketorolac tromethamine in-situ ocular hydro gel; prepara tion, characterization, and in-vivo evaluation

The aim of this work is to formulate Ketorolac tromethamine in a new ocular in situ hydro gel delivery system. Two polymers; Chitosan and Carbopol 940 were used in different concentrations for the preparation of the in situ hydro gels, all formulations exposed to visual examination, pH measurement, in-vitro release, rheological study, stability study, and in-vivo anti-inflammatory effect study on the inflamed eye of rabbits. Results showed that all formulations were clear and showed pH within the acceptable range, Chitosan 0.5%w/v gives the highest release rate, all formulae exhibited pseudoplastic flow with a thixotropic behavior, stability study showed that rate of drug degradation followed first order kinetics and 0.5% Chitosan based formula showed longer shelf life (2.532 year), the percent of unhealed ulcers of the inflamed eye of rabbits was 17.5% for 0.5% Chitosan in situ hydro gel compared to 55% for Acular eye drop (positive control). Statistical analysis of the data revealed significance difference between the tested formula and control solution at p <0.05. So this system that combines the advantages of both solutions and gels, such as accuracy and facility of administration of the former and prolonged residence time of the latter, also enhances the healing rate of Ketorolac tromethamine in ulcerative rabbit's eye compared to ocular eye drops.