Fabrication of a five-layer wound dressing containing chitosan-LL37 peptide for the treatment of EB wounds and deep exudate patients.

OBJECTIVES: This study aimed to develop and evaluate a multifunctional five-layer wound dressing that meets essential requirements for effective wound healing, including exudate absorption, antimicrobial activity, moisture retention, gas exchange, and non-damaging adhesion. The specific objective was to assess the antibacterial efficacy, biocompatibility, and wound-healing performance of a dressing incorporating chitosan--LL37 nanoparticles (CS-LL37 NPs). MATERIALS AND METHODS: A five-layer wound dressing was fabricated, consisting of a silicone adhesive layer, a polyurethane (PU) foam layer embedded with CS-LL37 NPs, a polypropylene diffusion layer, a cellulose-based retention layer, and a breathable, waterproof backing layer. The CS-LL37 NPs were incorporated into the PU layer, and their antibacterial activity and cytotoxicity were evaluated in vitro. The dressing's wound-healing performance, with and without CS-LL37 NPs, was assessed in vivo in a female Wistar rat model and compared with that of a commercial dressing (Mepilex Border). RESULTS: The developed five-layer dressing demonstrated effective exudate management, antimicrobial activity, and favorable healing conditions. In vivo results showed wound closure rates and histological outcomes comparable to those of the commercial dressing. The inclusion of CS-LL37 NPs enhanced antibacterial performance without inducing significant cytotoxicity, indicating good biocompatibility. CONCLUSION: The prepared five-layer wound dressing exhibited healing performance comparable to a commercially available product. The incorporation of CS-LL37 nanoparticles showed significant potential to improve treatment outcomes, particularly for exudative wounds, and may be a promising option for patients with chronic or fragile-skin conditions such as Epidermolysis Bullosa.