Inactivation of Microorganisms Using Cold Atmospheric Pressure Plasma with Different Temporal Discharge Characteristics

The effect of CAP on the dermatologic relevant bacteria E. coli, P. aeruginosa and the yeast C. albicans is studied in vitro. Two dielectric barrier discharge plasma devices with different temporal pulse characteristics are compared concerning their efficacy of germ inactivation. The study includes analyses of temperature, ozone concentration and UV radiation in the discharge gap as well as the influence on the growth medium in terms of temperature, pH value, NO2-, NO3-, and H2O2. The investigations are concluded by tests of growth inhibition, the morphological structure, and DNA damages of the microorganisms. The results demonstrate, that both devices are able to inactivate the germs, although the nanosecond pulsed plasma source has a higher efficacy based on a higher chemical discharge productivity.