An Environmentally Tolerant 5A Hydrogel with Photothermal Effect for Frostbite Treatment

Area of Science:

• Biomaterials Engineering
• Tissue Engineering
• Photothermal Therapy

Background:

• Rapid rewarming is standard frostbite treatment, but lacks effective adjunctive therapies.
• Conventional hydrogels freeze and lack rewarming ability, limiting their use in frostbite care.

Purpose of the Study:

• To engineer an environmentally tolerant photothermal hydrogel (5A-Gel) for frostbite treatment.
• To evaluate the anti-freezing, antioxidant, and photothermal properties of 5A-Gel.
• To assess the efficacy of 5A-Gel in a mouse frostbite wound model.

Main Methods:

• 5A-Gel synthesized using dynamic crosslinking of gelatin and tea polyphenols in a glycerol/water system.
• Characterization of hydrogel properties including anti-swelling, anti-freezing, anti-drying, antioxidant activity, and photothermal effects.
• In vivo evaluation of 5A-Gel in a mouse model of frostbite, assessing healing parameters.

Main Results:

• 5A-Gel demonstrated excellent anti-freezing, anti-swelling, and anti-drying properties, remaining flexible at -20 °C and 37 °C.
• The hydrogel exhibited concentration-dependent antioxidant activity and stable photothermal effects under laser irradiation.
• In vivo studies showed 5A-Gel significantly accelerated frostbite healing, promoting re-epithelialization, collagen deposition, and neovascularization while reducing inflammation.

Conclusions:

• 5A-Gel is a promising therapeutic platform for in situ frostbite treatment due to its unique properties.
• The developed hydrogel offers innovative principles for engineering high-performance materials for frostbite tissue injuries.
• Photothermal rewarming therapy with 5A-Gel presents a novel adjunctive strategy for frostbite management.