Zinc-doped carbon catalysts with peroxidase-like activity for Neutral-pH antibacterial applications via reactive oxygen species generation

Bacterial antibiotic resistance has evolved into a severe global public health threat, creating an urgent demand for non-antibiotic antibacterial strategies. Peroxidase (POD)-like nanozymes that generate bactericidal reactive oxygen species (ROS) from H 2 O 2 hold great promise for infection treatment; however, most carbon-based nanozymes suffer from intrinsically low catalytic activity and strict acidic pH preference, which severely restricts their antibacterial efficacy under physiological neutral microenvironments. Herein, zinc-doped carbon catalyst (Zn-CN) were synthesized within 2 min via an ultrafast one-pot microwave-assisted strategy, using 3,5-diamino-1,2,4-triazole as the carbon/nitrogen precursor and zinc nitrate hexahydrate as the dopant source. The synthesized Zn-CN exhibits intrinsic POD-like activity at neutral pH ( K m = 123.1 μM for H 2 O 2 ), and shows excellent salt tolerance and thermal stability. Upon co-treatment with low-dose H 2 O 2 (1 mM), Zn-CN exerts excellent antibacterial activity against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus by catalyzing ROS production to induce bacterial oxidative damage. The antibacterial efficacy was confirmed by colony counting, live/dead fluorescence staining, and intracellular ROS detection assays. This work provides a facile, energy-efficient approach for constructing neutral-pH active carbon nanozymes, offering a promising non-antibiotic platform to combat bacterial infections and antibiotic resistance.