Interstitial N-Strengthened Copper-Based Bioactive Conductive Dressings Combined with Electromagnetic Fields for...

This study introduces an innovative design and application of a nitrogen-interstitially strengthened Cu-Fe-Zn alloy bioactive dressing, which combines intrinsic bioactivity with electromagnetic stimulation to significantly accelerate wound healing. Interstitial nitrogen solid-solution Cu-Fe-Zn alloys were fabricated by integrating a low-oxygen controlled powder sintering process (N2(10%)/Ar (90%) atmosphere). Subsequent cold drawing generated ultrafine alloy wires (0.04 ± 0.005 mm) with a tensile strength of 1120 MPa, representing a 20.37% enhancement compared with conventional approaches. Utilizing an intelligent jacquard textile system, these Cu-Fe-Zn alloy wires and cotton yarn were woven into coaxial circular dressings tailored to wound morphology, allowing controlled directional current flow while exhibiting excellent biocompatibility and antibacterial properties. A customized electromagnetic coupling system, consisting of an electromagnetic field generator and Helmholtz coils, was developed. Integration with bioactive dressings resulted in a precise, multifunctional therapeutic platform. Electromagnetic stimulation achieved dual therapeutic outcomes: (1) activating the VEGF/p38-HSP27 signaling pathway, significantly enhancing angiogenesis (2.1-fold compared with controls) and promoting M2 macrophage polarization (+25.6%), thereby accelerating tissue regeneration; and (2) inhibiting the IL-17/NF-κB signaling axis, reducing TNF-α expression by 68%, thus effectively suppressing inflammation. This study offers essential technical insights for developing next-generation intelligent electromagnetic wound healing systems with substantial clinical potential.