Abstract
(Figure Presented) A direct-current, cold-atmospheric-pressure air plasma microjet (PMJ) sustained in a quasi-steady gas cavity in a liquid medium is used to inactivate Staphylococcus aureus (S. aureus) suspended in the liquid. The temperature and the pH value of the liquid change to steady-state values of about 400°C and 3.0-4.5, respectively, after 10 min of plasma treatment. The decrease in the pH is attributed to the reaction of NOx pro-duced in the air plasma with water at the gas-liquid interface. The concentrations of NO3- and NO2- are measured to be 37 mg.L-1 and 21 mg • L-1, respectively, after a 20 min of plasma treatment. Effective inactivation of S. aureus is found to start after the pH values decreases to about 4.5. This is attributed to the high oxidizing potential of the perhydroxyl radical (HOO) on the fatty acid in the cell membranes of the microor-ganisms in the liquid.
Original language | English (US) |
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Pages (from-to) | 231-236 |
Number of pages | 6 |
Journal | Plasma Processes and Polymers |
Volume | 7 |
Issue number | 3-4 |
DOIs | |
State | Published - Mar 22 2010 |
Keywords
- Bacteria
- Cell membranes
- Cold plasma
- Plasma microjets
ASJC Scopus subject areas
- Condensed Matter Physics
- Polymers and Plastics