Membrane destruction-mediated antibacterial activity of tungsten disulfide (WS₂)

Abstract

The antibacterial activities of tungsten disulfide (WS 2 ) nanosheets against two representative bacterial strains: Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus)were evaluated by colony-forming unit (CFU) studies. The WS 2 samples demonstrate a time and concentration dependent antibacterial activity (retardation of bacterial growth) for both bacterial strains.Morphology analyses reveal that WS 2 nanosheets adhere to the bacterial surfaces, resulting in robust inhibition of cell proliferation once a bacterium is fully covered with this nanomaterial. More importantly, the intimate contact of WS 2 nanosheets with a bacterium cell membrane can cause serious damage to the membrane integrity, and subsequently the cell death. On the other hand, the reactive oxygen species (ROS) generated by WS 2 nanosheets are found to be modest regardless of the WS 2 concentration, which is contradictory to the case of its structural analogue, MoS 2 , where ROS also play a significant role in its antibacterial activity. Taken together, our findings provide a detailed understanding of the antibacterial mechanism of WS 2 nanosheets, which might help promote their potential applications in biomedical fields.

Two‐Dimensional Materials for Antimicrobial Applications: Graphene Materials and Beyond

“…Liu et al. reported that the antibacterial activity of WS 2 nanosheets mainly originates from induced structural damage rather than ROS generation . However, because the authors did not show the GSH oxidation data, it is difficult to judge whether the membrane disruption is caused by a physical interaction or ROS‐independent oxidative damage.…”

Photocatalytic Water Disinfection of CVD Grown WS2 Monolayer Decorated with Ag Nanoparticles

“…While the direct use of sun light for photocatalytic bacterial disinfection might be attractive for low cost water treatment, the use of fluorescent light is more relevant for actual household applications to supply potable water. Antibacterial properties of WS 2 and rGO‐WS 2 nanosheet has also been investigated without using any light source . Luminescence activity has also been shown for WS 2 and MoS 2 with Ag nanoparticles based composite …”

Highly Stable and Antibacterial Two‐Dimensional Tungsten Disulfide Lamellar Membrane for Water Filtration

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