Design and fabrication of a multifunctional Zn-Fe@Ag nanocomposite for effective treatment of infections wounds

<title>Abstract</title> Infectious wounds, a common bacterial infection in clinical practice, often experience significantly delayed healing due to local bacterial colonization, macrophage polarization imbalance, and tissue regeneration inhibition, posing persistent challenges for clinical treatment. This study utilizes the principles of chemical coordination and electrostatic adsorption to construct a rod-shaped core-shell nanocomposite material (Zn-Fe@Ag) with stable physicochemical properties, potent antibacterial activity, macrophage polarization modulation, and enhanced repair cell proliferation. In the infected wound microenvironment, the material releases Zn²⁺, Fe³⁺, Ag⁺, and reactive oxygen species (ROS) in a controlled manner. Through synergistic action, it disrupts the bacterial cell wall, membrane, and ion channels, ultimately inducing irreversible bacterial death. Moreover, the released polyvalent metal ions modulate macrophage polarization, inhibit M1-type macrophage-mediated inflammatory responses, alleviate local oxidative stress, and promote angiogenesis and extracellular matrix deposition, accelerating wound healing. Overall, the Zn-Fe@Ag composite material achieves multiple functions-antibacterial, immune modulation, and repair cell regeneration-through synergistic effects, addressing the complex pathological microenvironment of infected wounds and offering a potentially translatable therapeutic strategy for efficient clinical repair of infectious wounds.