Polydopamine modified CuS@HKUST for rapid sterilization through enhanced photothermal property and photocatalytic ability

Because of the impressive evolution of the drug-resistant bacteria, the development of efficient, antibiotic-free agent is in great urgency. Herein, an efficient antibacterial agent, CuS@HKUST-polydopamine (PDA), was exquisitely designed, where the Cu-based metal-organic framework (MOF)—HKUST nanoparticles served as the porous frame, and the CuS was synthesized within the structure of the MOF through the process of in situ sulfuration, followed with polydopamine (PDA) covering the nanoparticles. The structure of the HKUST preventing the aggregation of the CuS nanoparticles, which improved their photothermal and photocatalytic properties. After covering with PDA, the nanoparticles’ abilities to produce heat and free radicals were further enhanced. This was because that the PDA itself could transform light into heat, which not only benefited the photothermal property, but also improved the photocatalytic property of the nanoparticles by accelerating the charge mobility. Moreover, the PDA could also transfer the photo-induced electrons fast and thus prevented the recombination of the photo-generated electron–hole pairs, which resulted in the enhanced ability to produce free radicals. As a result, under light irradiation, the antibacterial efficiency of the CuS@HKUST-PDA against Staphylococcus aureus ( S. aureus ) and Escherichia coli ( E. coli ) could reach 99.77% and 99.57%. Hence, the synthesized CuS@HKUST-PDA can be promising for anti-infection and sterilization application without using antibiotics. Graphical abstract