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

In this work, the efficiency of inactivation of a cold argon plasma jet at atmospheric pressure (appj) on the basis of a lowcurrent 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.