An advanced strategy for wound healing: Developing multifunctional β-chitosan dressings from squid pen waste

Wounds, particularly chronic ones, pose significant clinical challenges due to their persistent nature and high risk of complications, which severely compromise patient quality of life and impose substantial socioeconomic burdens. This study presents a novel and sustainable strategy for advanced wound management by developing multifunctional dressing platforms based on β-chitosan (β-CS) derived from squid pen waste. An optimized biochemical extraction process was developed to obtain high-purity β-CS with suitable crystallinity and an elevated deacetylation degree. To fully exploit the inherent bioactivity of β-CS, two novel wound healing platforms, namely an in-situ formed composite film (CSPF) and fast-deployable composite powder (CSPP), were fabricated by integrating β-CS with thermosensitive Poloxamer 407 (P407). In vitro characterization revealed that both formulations exhibited potent hemostatic capacity, broad-spectrum antibacterial activity, and outstanding hemocompatibility. In a murine full-thickness wound model, CSPF and CSPP significantly accelerated wound closure, enhanced collagen deposition, and promoted neovascularization. These dressings attenuated early inflammation through downregulation of key pro-inflammatory cytokines (IL-1β, IL-6, TNF-α), while activating the TGF-β/β-catenin pathway to facilitate fibroblast-to-myofibroblast transition and extracellular matrix remodeling. Furthermore, CSPF/CSPP enhanced VEGF-mediated angiogenesis, as evidenced by increased CD31⁺ microvessel density. By converting marine waste into bioactive therapeutics, this work advances sustainable biomaterial development and shifts wound care from passive coverage to active biological intervention.