Cold atmospheric argon plasma jet source and its application for bacterial inactivation

AbstractIn this work, the efficiency of inactivation of a cold argon plasma jet at atmospheric pressure (APPJ) on the basis of a low-current spark discharge into microorganisms with different characteristics of the cell walls was evaluated. Gram-negative bacteria Escherichia coli M۱۷, gram-positive bacteria Bacillus subtilis ۵۳۴ and Bacillus cereus IP ۵۸۳۲, and the yeast Saccharomyces cerevisiae were seeded on cultured Petri dishes. A plasma jet with an average power of ۰.۸۵ W and a flow rate of argon of ۶.۷ l/min was directed perpendicular to the Petri dishes with agar. The distance to the agar varied from ۰.۵ to ۳ cm, and the treatment time varied from ۵ to ۳۰۰ s. The efficiency of inactivation was assessed by measuring the area of inactivation zones (where there was no growth of microorganisms). It was shown that gram-negative bacteria E. coli M۱۷ is most susceptible to exposure to the plasma jet, and gram-positive bacteria B. cereus IP ۵۸۳۲ and yeast S. cerevisiae are most stable. It is established that an increase in the treatment time of plasma jets of a low-current spark allows effective inactivation of microorganisms over a much larger area.

Keywords:

Argon plasma , Microorganisms , Low , current spark , Plasma jets , Plasma inactivation , Atmospheric , pressure glow discharge