A H2O2-free depot for treating bacterial infection: localized cascade reactions to eradicate biofilms in vivo

Abstract

Peroxidase-like nanoparticles are promising materials to treat bacterial infection through catalyzing H₂O₂ into more toxic highly reactive oxygen species (hROS; such as hydroxyl radicals). However, all the reported related strategies, to the best of our knowledge, depend on the usage of extra H₂O₂, limiting the applications of peroxidase-like nanoparticles. Thus, it is necessary to develop peroxidase-based materials without extra H₂O₂. In this report, H₂O₂-free depots are prepared by integrating CaO₂ and hemin-loading graphene (H-G) into alginate (CaO₂/H-G@alginate). They can convert H₂O into hROS through localized cascade reactions at the site of bacterial infection and damage the main components of biofilms (bacteria, polysaccharides, proteins, and nucleic acids). Besides, the confined environment of depots can reduce the potential risk from H₂O₂ and improve the cascade catalytic activity. This is the first example of exploring peroxidase-like nanozymes without extra H₂O₂ to treat bacterial infection.