Double-crosslinked PNIPAM-based hydrogel dressings with adjustable adhesion and contractility

Area of Science:

• Materials Science
• Biomedical Engineering
• Regenerative Medicine

Background:

• Rapid wound closure is crucial for preventing infection and achieving scar-free healing after skin trauma.
• Traditional wound closure methods can be invasive and may lead to scarring.

Purpose of the Study:

• To develop novel hydrogel dressings with tunable contractility and adhesion for suture-free wound closure.
• To investigate the potential of these dressings in promoting scar-free wound healing.

Main Methods:

• Fabrication of hydrogel dressings using N-isopropyl acrylamide/sodium alginate/graphene oxide (PNIPAM-SA-GO).
• Incorporation of chitosan (CS) as a bridging polymer to enhance tissue adhesion.
• Utilizing near-infrared (NIR) thermal stimulation to control hydrogel contractility.
• Evaluation of adhesion strength and wound closure efficacy in mouse models.

Main Results:

• The PNIPAM-SA-GO hydrogels exhibited self-shrinking properties controllable by NIR thermal stimulation.
• Chitosan introduction achieved significant tissue-hydrogel adhesion strength (7.86 ± 1.22 kPa) with adjustable regional adhesion.
• Suture-free wound closure was successfully demonstrated in mouse models.
• Dressings reduced inflammatory cell infiltration and collagen deposition, promoting scar-free healing.

Conclusions:

• Double-crosslinked PNIPAM-based hydrogel dressings offer adjustable adhesion and contractility.
• These dressings represent a promising candidate material for achieving trackless wound healing.
• The developed hydrogels facilitate efficient wound closure and promote optimal tissue regeneration.