Surface-Modified Ni Nanoparticles for Enhanced Bacteria-Infected Wound Healing

Background: The abuse of antibiotics has led to antibiotic-resistant bacteria that threaten human health. Nickel, with strong antibacterial activity and low likelihood of inducing bacterial resistance, has become a preferred material for wound infection prevention. Methods: Surface-modified nickel nanoparticles were prepared via isopropanol modification. The dilution coating plate method was used to test their antibacterial activity against Gram-negative E. coli and Gram-positive MRSA. Fifteen mice were randomly divided into PBS, low-concentration and high-concentration nickel nanoparticle groups. An MRSA-infected wound model was established on mice. Wound healing was monitored, and tissue staining, organ observation, and blood biochemical tests were performed. Results: The antibacterial effect of nickel nanoparticles was concentration-dependent, inhibiting over 90% of both bacteria at 200 μg/mL. The high-concentration group achieved wound healing rates of 92.7 and 97.4% on days 5 and 7, with the highest collagen ratio (43.1%) and thinner epithelial thickness. No obvious organ lesions or significant blood biochemical differences were observed across groups. Conclusions: The surface-modified nickel nanoparticles have high biosafety, good antibacterial properties, and can effectively kill bacteria in the wound area, thus promoting the healing of bacterial infection.