chitosan-based thermosensitive hydrogel for ocular delivery of vancomycin and prednisolone

Abstract

In situ gel-forming hydrogels are one of the appealing systems for ocular drug delivery that can prolong the precorneal retention time, provide sustained release conditions as well as improve ocular bioavailability. These polymeric systems responsd to changes in special physicochemical factors in their environment and transfer from sol to gel phase. Chitosan was chosen for the preparation of thermosensitive hydrogel in the current project due to its unique properties including biocompatibility, biodegradability, mucoadhesive property, the positive charge that enables it to interact intimately with the. Chemical modification with polyethylene glycol was performed to improve the solubility and biological properties of chitosan. Objective In this study, we aim to develop thermo-responsible chitosan-based hydrogel and improve its properties by chemical modification to design ocular in-situ forming hydrogel containing vancomycin and prednisolone. Methods The in-situ gel formation of modified chitosan was fabricated using the appropriate ionic crosslinker agent. PEG-g-Chitosan hydrogel comprising vancomycin and prednisolone could be applied a co-delivery system to treat severe keratitis, especially after ophthalmic surgery. The formulation characterized in terms of physicochemical, structural, morphological, rheological properties, and in vitro drug release behavior. also was investigated for the in vitro cytotoxicity in HUVEC cells using MTT assay and microbiological effect in Staphylococcus aureus. Result The studies showed that the modified chitosan indicated water-solubility properties with the capability of fast hydrogel formation in mild condition. Further prepared hydrogels showed prolonged drug release behavior and have excellent efficacy in antibacterial activity in vitro with no cytotoxicity effect. Conclusion The developed hydrogel could be considered as a promising system for improving ocular drug bioavailability and reducing adverse effects via decrease indication frequency.