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Abstract Microbial biofilms are of critical concern because of their recalcitrance to antimicrobials. Cold atmospheric plasmas (CAP) represent a promising biofilm remediation strategy as they generate reactive oxygen and nitrogen species (RONS), but mechanisms underpinning CAP‐biofilm interactions remain unknown. We assess the impact of treatment modality on biofilm inactivation and show that CAP killing ofStaphylococcus aureusbiofilms is dependent on treatment conditions, including solution chemistry. In dry treatments, biofilms are locally ablated due to plasma‐produced O flux. For saline‐submerged biofilms, while we show that ClO−is generated at high concentrations in larger treatment volumes, CAP inactivation at low ClO−concentrations implicates other reaction pathways. Finally, we demonstrate CAP efficacy over conventional antimicrobials, underscoring its promise as a biofilm treatment approach.
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A hierarchal model for bacterial cell inactivation in solution by direct and indirect treatment using cold atmospheric plasmas
Abstract Cold atmospheric plasma devices have shown promise for a variety of plasma medical applications, including wound healing and bacterial inactivation often performed in liquids. In the latter application, plasma-produced reactive oxygen and nitrogen species (RONS) interact with and damage bacterial cells, though the exact mechanism by which cell damage occurs is unclear. Computational models can help elucidate relationships between plasma-produced RONS and cell killing by enabling direct comparison between dissimilar plasma devices and by examining the effects of changing operating parameters in these devices. In biological applications, computational models of plasma-liquid interactions would be most effective in design and optimization of plasma devices if there is a corresponding prediction of the biological outcome. In this work, we propose a hierarchal model for planktonic bacterial cell inactivation by plasma produced RONS in liquid. A previously developed reaction mechanism for plasma induced modification of cysteine was extended to provide a basis for cell killing by plasma-produced RONS. Results from the model are compared to literature values to provide proof of concept. Differences in time to bacterial inactivation as a function of plasma operating parameters including gas composition and plasma source configuration are discussed. Results indicate that optimizing gas-phase reactive nitrogen species production may be key in the design of plasma devices for disinfection.
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- PAR ID:
- 10524977
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of Physics D: Applied Physics
- Volume:
- 57
- Issue:
- 40
- ISSN:
- 0022-3727
- Format(s):
- Medium: X Size: Article No. 405207
- Size(s):
- Article No. 405207
- Sponsoring Org:
- National Science Foundation
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