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Synthesis of new, highly active antibacterial agents has become increasingly important in light of emerging antibiotic resistance. In the present study, ZnO/graphene quantum dot (GQD) nanocomposites were produced by a facile hydrothermal method and characterized by an array of microscopic and spectroscopic measurements, including transmission electron microscopy, X-ray photoelectron spectroscopy, UV-vis and photoluminescence spectroscopy. Antibacterial activity of the ZnO/GQD nanocomposites was evaluated with Escherichia coli within the context of minimum inhibitory concentration and the reduction of the number of bacterial colonies in a standard plate count method, in comparison to those with ZnO and GQD separately. It was found that the activity was markedly enhanced under UV photoirradiation as compared to that in ambient light. This was ascribed to the enhanced generation of reactive oxygen species under UV photoirradiation, with minor contributions from membrane damage, as manifested in electron paramagnetic resonance and fluorescence microscopic measurements. The results highlight the significance of functional nanocomposites based on semiconductor nanoparticles and graphene derivatives in the development of effective bactericidal agents.
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Capacitively Coupled Plasma from Laser-Induced Graphene Points to Ozone as the Major Mediator of Antibacterial Activity
Low-temperature plasma is an emerging approach for the treatment of bacterial infections. Nonchemical treatments such as cold plasma offer potential solutions to antibiotic resistance. We investigated the use of laser-induced graphene as aninexpensive, lightweight, and portable electrode for generating cold plasma. At the same time, the mechanism or molecular mediators of cold plasma-induced antibacterial activity remain poorly understood. This study validates graphene as an efficient structure for producing therapeutic cold plasma, and this study also indicates that ozone is the primary mediator of antibacterial activity in graphene-mediated cold plasmas for bacterial growth under the conditions studied.
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- Award ID(s):
- 2203948
- PAR ID:
- 10549838
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- Volume:
- 15
- Issue:
- 39
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 45601 to 45605
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsami.3c09216
