Optimization of in-situ Nanoparticulate Gel of Ofloxacin using Factorial Design to Improve Treatment Strategy for Conjunctivitis and Corneal Ulcers

Background: One of the main problems in ophthalmic drug delivery is the rapid elimination of conventional liquid eye drops from the eye due to rapid tear turnover resulting precorneal loss because of irritation caused by the drug preparation from large volume of the administered eye drop (~50 μl), a very small amount i.e. <5% of the dosage actually penetrates and is able to reach intraocular tissues. Ofloxacin (OFL), a fluoroquinolone drug is used for the treatment of conjunctivitis and corneal ulcers and it is given quarterly in a day because its bioavailability is very low. The present study was designed to increase the ocular residence time of drug by formulating nanoparticulate in-situ gel for ensuring low irritation, better release and compatibility with ocular tissue. Materials and Methods: Initially, OFL nanoparticles were prepared using single emulsion solvent evaporation method and evaluated for various evaluation parameters. Based on the results, an optimized batch (B3) was selected by applying factorial design; which was further converted into in-situ gel. Results: Results of evaluation parameters revealed that optimized batch (B3) showed significant (p=0.0001 and p=0.0090) increased in particle size and entrapment efficiency in comparison to rest batches. Moreover, nanoparticulate in-situ gel showed satisfactory results. Conclusion: Hence, Ofloxacin nanoparticulate in-situ gel thus formulated showed controlled drug release with lesser dosing frequency.