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 of Staphylococcus aureus biofilms 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.
Bibliographical noteFunding Information:
The authors acknowledge the support of National Science Foundation through Award PHY 2020695, the U.S. Department of Energy through Award DE‐SC 0016053, and the University of Minnesota College of Veterinary Medicine Comparative Medicine Signature Program.
© 2022 The Authors. Plasma Processes and Polymers published by Wiley-VCH GmbH.
- Staphylococcus aureus
- cold atmospheric plasma