Combined Characterization of a Plasma Jet: FTIR, Chemical Surveys and Antibacterial Effect

Atmospheric pressure low power plasma jets operating in noble gases are a widespread tool in plasma medicine studies. We present experimental results obtained in one such device, which combine physical, chemical and biological measurements to assess the effectiveness in production of reactive oxygen and nitrogen species and in inactivation of Escherichia coli, a model microorganism. We proved that it exists a threshold effect on the source control parameters, defining a voltage level which has to be exceeded in order to obtain effective bacteria inactivation. This result is discussed in terms of the reactive species produced within the plasma and in treated water.