Cu–ZnO Composite Nanoparticles Loaded Catalytic Fiber Efficiently Inactivates Bacteria by Generating Active Species Without Needing Light

As one of extensively used photocatalysts, zinc oxide nanoparticles (ZnO NPs) can generate free radicals under proper light irradiation, thereby achieving excellent antibacterial performance. However, the requirement of using light activation has limited its application to wider fields. In addition, nano-copper (Cu NPs) have gradually attracted the attention of researchers due to their excellent antibacterial properties. However, the high surface activity of nanoparticles makes them easy to agglomerate, and Cu NPs are easily oxidized, which affect the antibacterial activity. By synthesizing Cu–ZnO composite nanoparticles and loading the particles onto low melting-point polyethylene terephthalate (LMPET) fibers, we have developed a novel catalytic fiber (Cu–ZnO@LMPET) that can generate active species without needing light. It was found that Cu–ZnO@LMPET fibers with the copper content of 5 wt% (vs. ZnO NPs) or above could achieve 99% antibacterial effects on S. aureus and E. coli under dark conditions. Moreover, the antibacterial rates against E. coli and S. aureus could still be larger than 97 and 98%, respectively, even if the fibers were washed 50 times. In-vitro biocompatibility assessment also displayed that the as-prepared fibers had superb cytocompatibility. These results indicate that our developed fibers have highly efficient antibacterial properties, good washing resistance and high stability. Thus, our work has shed new light on the use of Cu–ZnO NPs for antibacterial purposes. Graphical Abstract