Injectable Click Chemistry-based Bioadhesives for Accelerated Wound Closure

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Surgical Innovation

Background:

• Existing tissue adhesives often exhibit cytotoxicity, insufficient adhesive strength, and high costs, limiting their surgical utility.
• Sutures are a traditional method for wound closure but can cause tissue damage and scarring.

Purpose of the Study:

• To develop novel chitosan-based bioadhesives using click chemistry for enhanced surgical wound closure.
• To optimize bioadhesive properties including gelation time, adhesive strength, and biocompatibility.

Main Methods:

• Fabrication of bioadhesives using a copper-free click chemistry reaction between trans-cyclooctene (TCO) and tetrazine (Tz) functionalized chitosan.
• Incorporation of 4-arm polyethylene glycol propionaldehyde (PEG-PALD) as a co-crosslinker to tune mechanical properties and swelling.
• Evaluation of gelation kinetics, adhesive strength, swelling ratio, pore size, in vitro cytotoxicity, and in vivo wound healing in a mouse model.

Main Results:

• Bioadhesives achieved gelation in under 2 minutes, suitable for surgical settings.
• Optimized bioadhesives exhibited 2.3 times greater adhesive strength compared to fibrin glue.
• Tunable swelling ratios and pore sizes allow for drug encapsulation and cell seeding.
• No significant in vitro cytotoxicity was observed.
• Chitosan bioadhesives demonstrated faster wound closure and promoted healing in a mouse model compared to fibrin glue.

Conclusions:

• The developed click chemistry-based chitosan bioadhesives offer a promising alternative to conventional wound closure methods.
• These bioadhesives exhibit favorable properties including rapid gelation, high adhesive strength, injectability, low cytotoxicity, and enhanced wound healing.
• The tunable nature of the bioadhesives supports applications in drug delivery and regenerative medicine.