Mu Yun-Long, He Qing, Li Chun-Yan, Sheng Da, Wu Song-Hai, Liu Yong, Ren Hai-Tao, Han Xu
Tianjin Key Laboratory of Chemical Process Safety and Equipment Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, PR China.
Instrument analysis and testing center, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, PR China.
Langmuir. 2024 Aug 13. doi: 10.1021/acs.langmuir.4c00984.
Although precise regulation of the crystalline structures of metal oxides is an effective method to improve their antibacterial activities, the corresponding mechanisms involved in this process are still unclear. In this study, three kinds of cuprous oxide (CuO) samples with different structures of cubes, octahedra, and rhombic dodecahedra (c-CuO, o-CuO, and r-CuO) have been successfully synthesized and their antibacterial activities are compared. The antibacterial activities follow the order of r-CuO > o-CuO > c-CuO, revealing the significant dependence of the antibacterial activities on the crystalline structures of CuO. Quenching experiments, as well as the NBT and DPD experiments indicate that ≡Cu─OO superoxo and ≡Cu─OOH peroxo, instead of •OH, O, and HO, are the primary oxidizing species in the oxidative damage to . Raman analysis further confirms the presence of both ≡Cu─OO superoxo and ≡Cu─OOH peroxo on the surface of r-CuO. On the other hand, the NCP experiment reveals that Cu, instead of Cu, also contributes to the antibacterial process. This study provides new insight into the antibacterial mechanisms of CuO.
