Morphological modulation of copper-doped BiOBr nanomaterial with improved visible light photocatalytic activity for drug-resistant bacteria elimination

Abstract

Bacterial infections accompanied by aggravated bacterial resistance in surrounding environment and healthcare facilities have remained threatening to public health, which demands developing efficient and safe disinfection methods devoid of the overuse of antibiotics. Here, in an attempt to build photocatalytic bacterial inactivation strategy, copper doped BiOBr (Cu@BOB) with modulated morphologies were obtained via solvothermal synthesis. As compared to that of Cu@BOB-sheet, the enhanced doping efficiency of Cu²⁺ was found in Cu@BOB-sphere. Meanwhile, the latter possesses more (110) facet exposure, oxygen vacancy and efficient separation of e^-/h⁺ pairs, leading to its superior photocatalytic antibacterial effect under visible light. Particularly, singlet oxygen, photo-induced holes and electrons were shown to be mainly involved in the photocatalytic disinfection process, which may disrupt cellular structures of Escherichia coli (E. coli), and Methicillin-Resistant Staphylococcus aureus (MRSA). Finally, transcriptomic analysis of MRSA treated with Cu@BOB-sphere revealed that not only the oxidative stress was triggered and the ribosome biosynthesis, translation, amino acid biosynthesis and metabolism were interrupted in MRSA, but genes related to virulence factor generation were down-regulated, pointing to the effective role of Cu@BOB-sphere to minimize drug-resistance. Therefore, the constructed visible light-responsive Cu@BOB photocatalyst with controllable morphology paves an ecofriendly and efficient strategy to combat drug-resistant bacteria.