Ionic-bridge engineered α-lactalbumin nanoparticles integrated into electrospun nanofibers for controlled growth factor delivery and burn wound repair

Protein-based nanoparticles hold great promise for bioactive molecule delivery, but conventional fabrication routes are often complex and rely on surfactants or organic solvents. Here, we reported a crosslinker-free strategy to engineer α-lactalbumin (ALA) nanoparticles via Ca²⁺ mediated ionic bridging and electrospraying, enabling efficient encapsulation of acidic fibroblast growth factor (aFGF). These aFGF@ALA nanoparticles were subsequently integrated into electrospun poly(vinyl alcohol) (PVA) nanofiber matrices to construct hybrid dressings (aFGF@ALA NPs/PVA ENMs). The resulting nanostructures combine the structural support of nanofibers with the controlled release capacity of protein nanoparticles, yielding a synergistic platform for therapeutic delivery. In vitro, the hybrid dressings promoted fibroblasts and keratinocytes proliferation and migration with excellent cytocompatibility. In vivo, they accelerated burn wound repair by enhancing re-epithelialization, collagen I/III remodeling, and angiogenesis. This work introduces a facile and generalizable strategy for designing functional protein-based nanoparticles and demonstrates their integration with nanofiber scaffolds as a versatile platform for growth factor delivery and tissue regeneration.