In situ formation of injectable chitosan-gelatin hydrogels through double crosslinking for sustained intraocular drug delivery.

Mater Sci Eng C Mater Biol Appl

Division of Clinical Cell Therapy, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan. Electronic address:

Published: July 2018

Rapid clearance and low ocular bioavailability are drawbacks of conventional ophthalmic eye drops. To increase the ocular drug resistance time and improve efficacy, an in situ forming and thermosensitive chitosan-gelatin hydrogel was developed. The feasibility of using this hydrogel as a topical eye drop formulation for sustained release of timolol maleate was evaluated. The flexible hydrogel that was co-crosslinked with β‑glycerophosphate disodium salt hydrate (β-GD) and genipin showed a fast gel formation at 37 °C. The swelling properties and in vitro biodegradation characteristics showed a strong relationship with the initial genipin concentration. In vitro release profiles demonstrated that crosslinking with genipin reduced the release rate of entrapped model drugs and timolol maleate. In vitro cytotoxicity tests showed that the hydrogel was non-toxic to Chinese hamster fibroblast V79 cells. The hydrogel was further applied as eye drop formulations for sustained release of timolol maleate to reduce intraocular pressure (IOP). A fast gel formation was observed after instilling the chitosan-gelatin solution into the lower conjunctival sac of the rabbit eyes, and the in situ formed hydrogels protected the drugs from clearance by tears, and released the drugs in a sustained manner. Furthermore, administration of timolol maleate containing chitosan-gelatin hydrogels showed a long-lasting and effective IOP lowering efficacy for up to 24 h compared with the conventional eye drops. These results suggested that β-GD and genipin co-crosslinked chitosan-gelatin hydrogels could be a useful ocular drug delivery platform with enhanced therapeutic effects and reduced side effects.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.msec.2018.02.022DOI Listing

Publication Analysis

Top Keywords

timolol maleate
16
chitosan-gelatin hydrogels
12
drug delivery
8
eye drops
8
ocular drug
8
eye drop
8
sustained release
8
release timolol
8
β-gd genipin
8
fast gel
8

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!