Journal of Theoretical and Applied Physics (JTAP) Cold atmospheric argon plasma jet source and its application for bacterial inactivation Volume 13, 2019 Issue 2, May and June 2019 2023 11 17 Cold atmospheric argon plasma jet source and its application for bacterial inactivation 10.1007/s40094-019-0326-3 EN Journal Article 2023 11 17 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 M17, gram-positive bacteria Bacillus subtilis 534 and Bacillus cereus IP 5832, and the yeast Saccharomyces cerevisiae were seeded on cultured Petri dishes. A plasma jet with an average power of 0.85 W and a flow rate of argon of 6.7 l/min was directed perpendicular to the Petri dishes with agar. The distance to the agar varied from 0.5 to 3 cm, and the treatment time varied from 5 to 300 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 M17 is most susceptible to exposure to the plasma jet, and gram-positive bacteria B. cereus IP 5832 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.