Improvement of Ocular Efficacy of Levofloxacin by BioadhesiveChitosan Coated PLGA Nanoparticles: Box-behnken Design,In-vitro Characterization, Antibacterial Evaluation andScintigraphy Study

Conjunctivitis is considered as a common infection of ocular surfaces. eye drop is mostcommonly used for treatment of conjunctivitis, but has some drawback like 95% drug eliminatedafter administration. administration of levofloxacin to the anterior site in form of chitosan coatedpoly (lactic-co-glycolic acid) nanoparticles (lfv-cs-plga-nps) expected to overcome theseproblem and increasing corneal contact time and permeability for effective treatment of bacterialconjunctivitis. the nanoparticles were developed by single emulsion solvent evaporation techniqueand optimized for different variables (chitosan, poly (lactide-co-glycolic acid) and polyvinylalcohol concentration) by employing three factors, three levels box–behnken statistical design.the nanoparticles were evaluated for particle size, drug loading, entrapment efficiency, drugrelease, ex-vivo permeation, ocular tolerance, antimicrobial study, confocal laser microscopy, andgamma scintigraphy study. the particle size and pdi of the optimized nanoparticles were 169.968± 15.23 nm and 0.13 ± 0.03, respectively, where as entrapment efficiency and drug loading is49.54 ± 2.43% and 11.29 ± 2.13% with extended release profile and strong mucoadhesion. dscdata indicated levofloxacin formed molecular dispersion within coated nanoparticles. cornealflux showed significantly (p < 0.05) higher permeation as compared to marketed formulation.formulation was nonirritant and possessed good antibacterial activity. gamma scintigraphyshowed slow drainage compared to drug solution, indicating reduction in nasolachrymal drainage.the gamma scintigraphy study indicated the cs coated plga-nps have high corneal residencetime as compared to drug solution. so, it is revealed that lfv-cs-plga-nps increase the drugconcentration over ocular tissue and potential usefulness for sustained drug delivery.