Formulation and optimization of levofloxacin loaded chitosan nanoparticle for ocular delivery: In-vitro characterization, ocular tolerance and antibacterial activity

In this study, chitosan nanoparticles (CH-NPs) were used to encapsulate antibacterial agent levofloxacin for the treatment of ocular infection. The chitosan nanoparticles were prepared by ionic gelation method using chitosan and sodium tripolyphosphate. The developed formulations were evaluated for various physicochemical parameters and optimized formulation was converted into the sol-gel system to enhance the corneal residence time. The developed formulations showed the particle size in nanometric range with high encapsulation, and loading. HET-CAM test and histopathology of cornea demonstrated that optimized formulation was found to be non-irritant and safe for topical ophthalmic use. The antimicrobial study revealed that the developed formulation possesses higher antibacterial activity against P. aeruginosa, and S. aureus. The pharmacoscintigraphic study result revealed the reduced corneal clearance, naso-lachrymal drainage as well as higher retention of LFX in comparison to LFX solution. Our results concluded that levofloxacin loaded chitosan nanoparticles in situ gel system found to be an efficient carrier for ocular delivery of levofloxacin.