A cost-effective, fast cooling, and efficient anti-inflammatory multilayered topological hydrogel patch for burn wound first aid

First-aid burn wound patches play an essential role in reducing mortality by preventing hyperthermia and resisting wound infection. However, existing products still suffer from inferior cooling performance, limited therapeutic effect, weaker wound protection, and/or high cost, which hinder their widespread application in market. Herein, we design and fabricate a cost-effective multilayered topological hydrogel-based first-aid burn wound patch (FBP) for rapid cooling, efficient anti-inflammation, and wound protection. Such a hydrogel patch is fabricated from a polyacrylamide-chitosan (PAAm-CS) hydrogel as the soft antibacterial layer integrated with a topological poly(vinyl alcohol)-chitosan (PVA-CS) hydrogel as the stretchable cooling layer, as well as thin polyethylene films as encapsulated layers to prevent dehydration. As-fabricated FBP exhibits a unique combination of intriguing mechanical, thermal, and biological properties, including softness (Young’s modulus of 83 kPa), stretchability (fracture stain over 106%), high thermal conductivity (0.54 W m−1 K−1), instant cooling, effective antibacterial activity (96.2% for S. aureus, 92.2% for E. coli), and excellent biocompatibility (94.04% cell viability at 20 mg mL−1 extract in 24 h). A second-degree scald rat model further demonstrates that fast-cooling and anti-inflammatory FBP can effectively reduce the tissue damage and inflammation levels by showing less edema formation and higher collagen/blood vessel ratios. With a set of these interesting performances, the FBP may be useful as a first-aid burn wound product to alleviate patients’ sufferings and even rescue more lives in critical situation.