Comparison of CO production and Escherichia coli inactivation by a kHz and a MHz plasma jet.

As carbon monoxide has a broad spectrum of biological activities, its production by plasma is a significant advantage in medicine. This paper presents a comparative study of the CO production of two plasma jets: a MHz‐jet and a kHz‐jet. Both were fed with a helium gas with CO2 ${\text{CO}}_{2}$ admixture (0%–1%). CO was produced by CO2 ${\text{CO}}_{2}$ dissociation and its maximal concentration was hundreds of parts per million, which is safe for clinical applications. For the same specific energy input, the CO production was more efficient for the kHz‐jet than the MHz‐jet. Both had antibacterial properties on Escherichia coli, and the addition of CO2 ${\text{CO}}_{2}$ improved them for the MHz‐jet, while it reduced them for the kHz‐jet. [ABSTRACT FROM AUTHOR]