Characterization and Evaluation of Layered Bi₂WO₆ Nanosheets as a New Antibacterial Agent

Background: Pathogenic microorganisms are causing increasing cases of mortality and morbidity, along with alarming rates of ineffectiveness as a result of acquired antimicrobial resistance. Bi₂WO₆ showed good potential to be used as an antibacterial substance when exposed to visible light. This study demonstrates for the first time the dimension-dependent antibacterial activity of layered Bi₂WO₆ nanosheets. Materials and methods: The synthesized layered Bi₂WO₆ nanosheets were prepared by the hydrothermal method and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and Raman and Fourier transform infrared spectroscopy (FTIR). Antibacterial and antibiotic-modulation activities were performed in triplicate by the microdilution method associated with visible light irradiation (LEDs). Results: Bi₂WO₆ nanosheets were effective against all types of bacteria tested, with MIC values of 256 μg/mL against Escherichia coli standard and resistant strains, and 256 μg/mL and 32 μg/mL against Staphylococcus aureus standard and resistant strains, respectively. Two-dimensional (2D) Bi₂WO₆ nanosheets showed antibacterial efficiency against both strains studied without the presence of light. Conclusions: Layered Bi₂WO₆ nanosheets revealed dimension-dependent antibacterial activity of the Bi₂WO₆ system.