Cu(II)@ZIF-8 nanoparticles with dual enzyme-like activity bound to bacteria specifically for efficient and durable bacterial inhibition

Abstract

The spread of drug-resistant bacteria has significantly reduced the effectiveness of current antibiotics and poses a growing global challenge. Therefore, there is an urgent demand to develop novel antimicrobial strategies to reduce the use of antibiotics and the spread of drug-resistant bacteria. In this work, we constructed a novel Cu(II)@ZIF-8 nanoenzyme material to realize efficient inhibition effect on bacteria. In vitro antibacterial experiments of the composites demonstrated their excellent antibacterial performance against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In particular, the minimum inhibitory concentration (MIC) against S. aureus was only 64 μg/mL, which was four times the antibacterial activity of ZIF-8 NPs. Antibacterial mechanism studies revealed that Cu(II)@ZIF-8 NPs possessed both oxidase-like and peroxidase-like activities and specifically bound to bacterial cell walls. Such properties facilitated the in-situ production of reactive oxygen species within bacteria, greatly increasing the antibacterial activity with minimum damage to normal biological tissues. In vitro biocompatibility experiments revealed that Cu(II)@ZIF-8 NPs had excellent hemocompatibility and cytocompatibility. Therefore, this research provides a new strategy for the design and preparation of novel efficient and safe antibacterial materials in the future.