DEVELOPMENT AND CHARACTERIZATION OF TOPICAL OPHTHALMIC FORMULATIONS CONTAINING LUTEIN-LOADED MUCOADHESIVE NANOPARTICLES

Objective: To develop and characterize a topical ophthalmic formulation containing chitosan-dextran sulfate nano particles (CDNs) for enhanced ocular bioavailability and stability of lutein.Methods: Lutein-loaded CDNs (LCDNs) were prepared by polyelectrolyte complexation employing oppositely charged polymers, chitosan and dextran sulfate. Effects of the polymer mass ratios, the total amount of polymers, and the amount of EDC and PEG400 on their physicochemical properties as well as the drug release profiles were investigated. The physicochemical stability of LCDNs dispersed in various ophthalmic vehicles and the accompanying microbial contamination were also evaluated.Results: LCDNs possessed a mean size of ~400 nm with a positive surface charge of+30 mV and entrapment efficiency up to 75%. Dissolution profiles followed a Higuchi's square root model, indicating a diffusional release mechanism. LCDNs dispersed in Feldman ophthalmic buffer showed good physical stability with no microbial contamination. The chemical stability of lutein was significantly improved in LCDNs and further improved by the addition of antioxidant in the ophthalmic vehicle.Conclusion: The ophthalmic formulation containing LCDNs, developed in this work, has characteristics suitable for application in ocular surface drug delivery systems.Keywords: Chitosan, dextran sulfate, Nanoparticles, Ophthalmic vehicle, Lutein