Linear microdischarge jet for microbiological applications

Abstract

A new type of linear cold atmospheric-pressure plasma source, the plasma razor jet, was devised. Operational parameters, such as the lowest required power for igniting the plasma, the power below which the plasma is extinguished, and the power at which the discharge arc occurs, were determined. Optical emission spectra and the treated surface temperature were also investigated. Based on the diffuse model for linear light sources, the distribution of plasma irradiation was calculated. It was found that the plasma razor jet is well fit for surface treatment, providing sufficiently uniform irradiation during scanning. This device was tested as a cold atmospheric-pressure plasma source for treatment of pathogenic fungi, such as Candida albicans and Prototheca zopfii. To compare the effectiveness of the plasma in eradicating various microorganisms, the concept of minimal lethal dose (Dmin) is introduced.