Inactivation of E. coli by nano-Cu/MWCNTs combined with hydrogen peroxide

•The antibacterial ability of nCu-MWCNTs combined with H2O2 was evaluated.•nCu-MWCNTs/H2O2 exhibited superior antibacterial effect against E. coli.•Synergistic interaction happened between nano-Cu, MWCNTs and H2O2.•MWCNTs promoted the electron transfer of nano-Cu and promoted the generation of OH.•Copper ions and OH contributed the deactivation ability.

This paper aims at the study on the antibacterial activity of nCu-MWCNTs combined with H2O2 against gram-negative bacteria Escherichia coli (E. coli). The antibacterial ability of nCu-MWCNTs/H2O2 was evaluated by traditional surface plating method, fluorescence and SEM imaging, and the effects of variables (contacting time, dose of nCu-MWCNTs and dose of H2O2) were investigated. By comparing with other five processes including H2O2, MWCNTs, nCu-MWCNTs, MWCNTs/H2O2 and nCu/H2O2, nCu-MWCNTs and H2O2 was proved to have superlative antimicrobial effectiveness against E. coli. The role of nano-Cu, MWCNTs and H2O2 in the antimicrobial activity of nCu-MWCNTs/H2O2 was clarified. The release of copper ions and formation of hydroxyl radicals (OH) both contributed the antibacterial ability of nCu-MWCNTs/H2O2 system. And MWCNTs as the support might be able to promote the electron transfer in nCu-MWCNTs for copper ion release.

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