Preparation of Multifunctional Hydrogel Loaded with Isochlorogenic Acid A/Fe3+ Co-Assembled Nanoparticles and Its Application in Skin Wound Repair

The skin serves as the largest protective barrier organ of the human body and is easily impaired by trauma, infection and chronic diseases. Efficient wound dressings are indispensable for repairing infected wounds. Isochlorogenic acid A (IAA), the core active ingredient of Shanyinhua, has superior anti-inflammatory and antibacterial effects. However, low water solubility and weak structural stability restrict its direct application in wound treatment. In this work, IAA@Fe(III) nanoparticles (IAA@Fe(III) NPs) were synthesized through self-assembly and loaded into cross-linked amylopectin (Amy)/carboxymethyl chitosan (CMCS) (AC hydrogel) to construct Amy/CMCS@NPs composite dressings. Characterizations demonstrated that nanoparticles displayed a uniform spherical shape with a size of 114.20 ± 2.29 nm and stable coordination. The hydrogel featured a dense porous structure and outstanding mechanical performance, self-healing ability, adhesion, and swelling properties. In vitro tests proved that 50 mg/mL composite hydrogel exerted nearly 100% bacteriostatic activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with good biocompatibility, and enhanced cell migration capacity. In vivo assays indicated an 86.5% wound healing rate at day 7. This dressing could downregulate Tumor Necrosis Factor-α (TNF-α) and Interleukin-1β (IL-1β), upregulate Cluster of Differentiation 31 (CD31) and Vascular Endothelial Growth Factor (VEGF), and accelerate wound repair. This study provides a theoretical and experimental basis for the exploitation of IAA-based wound dressings and high-value utilization of Shanyinhua resources.