Synthesis and in Vitro Evaluation of Bioactive Chitosan-Coated Bimetallic Zeolitic Imidazole Frameworks (CS@ZIF-Ni) for Antibacterial and Wound Healing Applications

The infection with multiple-drug-resistant bacteria and fungi has become a significant challenge in wound care management. Microbial infections significantly increase mortality rates and healthcare costs for patients with diabetic wounds. Therefore, the design of effective antimicrobial materials for wound healing is critically important. Zeolitic imidazole frameworks (ZIFs) are highly tunable and effective materials for biomedical applications. In this study, we present a chitosan-coated bimetallic ZIF-Ni nanocomposite designed for antimicrobial and wound healing applications. The material characteristics of the CS@ZIF-Ni nanocomposite were systematically investigated using various spectroscopic and microscopic techniques. The surface coating of the biopolymer chitosan enhances the biological activity and biocompatibility of the CS@ZIF-Ni nanocomposite. Antimicrobial assays confirmed that the combination of bimetallic zeolitic imidazole and chitosan effectively eradicates multidrug-resistant pathogenic bacteria and fungi. Results from cytotoxicity assays on human skin cells indicated that the CS@ZIF-Ni is a highly biocompatible material. The presence of zinc and nickel promotes reactive oxygen species (ROS)-mediated microbial cell death and creates optimal conditions for cell regeneration. Additionally, the chitosan bioactive molecules stimulate antimicrobial activity and enhance the migration rate of wounded cells. The synergistic effects of CS@ZIF-Ni, including its high stability, biosafety, antimicrobial efficacy, and ability to support cell regeneration based on in vitro experiments, make it an excellent therapeutic option for wound care management. The findings of this study suggest that the chitosan-coated ZIF-Ni nanocomposite improves antibiotic efficacy against human infectious pathogens and may serve as a valuable material for antimicrobial therapy and wound healing applications.

Graphical Abstract