A targeted nanozyme based on multiple porphyrins for enhanced photodynamic antibacterial application

Abstract

• The targeted nanozyme has the catalase- and peroxidase-like activities. • This phenylboronic acid-functionalized nanozyme can capture the bacteria. • The nanozyme can decompose the overexpressed H 2 O 2 to O 2 and generate ROS in situ. • The nanozyme can alleviate hypoxia and enhance PDT for bacterial infection ulcers. High H 2 O 2 content at the bacterial infection site causes irreversible damage to DNA, RNA and proteins, and influences intracellular signaling through essential signaling proteins that control cell proliferation. Catalase can decompose H 2 O 2 to produce O 2 in situ, which is an ideal strategy to reduce H 2 O 2 in the infectious tissue. In this work, a novel targeted nanozyme Co Ⅱ TBPP(bpy) is precisely synthesized by utilizing supramolecular self-assembly. The prepared nanozyme exhibits excellent ability to capture bacteria due to its phenylboronic acid groups and has broad-spectrum antibacterial efficiency through the synergy of PDT, the change of membrane permeability and the peroxidase-like • OH production. In addition, Co Ⅱ TBPP(bpy) has significant effect on anti-inflammatory and promoting wound healing, which is proved in E. coli -infected rat ulcers model in vivo and shows very low cytotoxicity to normal mammalian cells. With further development and optimization, as a new type of antibacterial nanozyme, Co Ⅱ TBPP(bpy) has a great potential for the treatment of wound infections.