Remote Oxygen and Nitrogen Plasma Inactivation of Staphylococcus aureus: Effects and Mechanisms

Abstract

The distribution of active species in remote oxygen and nitrogen plasma and the germicidal effect (GE) of Staphylococcus aureus on the surface of medical poly(tetrafluoroethylene), polyvinyl chloride and polyethylene terephthalate films, which had been widely used in medical devices, were studied. The results showed that the concentration of electrons and ions decreased rapidly with increasing the distance from the center of induction coil, which approximated to 0 at 40 cm, whereas the concentration of both oxygen and nitrogen radicals reduced slowly, which decreased 20% within 40 cm. Fast etching action on cell membrane by electrons, ions and radicals are primary reasons of oxygen and nitrogen plasma inactivation, which leads to the cellular contents effuse and engender bacteria death, however, the GE of UV radiation in remote plasma is feebleness comparatively. The GE also depends on the oxidation of gas for discharge and the surface characters of material.

Corona Discharge Plasma Jet Inactivates Food-borne Pathogens Adsorbed onto Packaging Material Surfaces

“…The mode of action of plasma species is more complex in microbial inactivation. Fast etching actions of electrons, ions and radicals on cell membranes are known to induce bacteria death, and have been the primary reasons for oxygen and nitrogen plasma inactivation . The inelastic collisions are responsible for the effective energy transfer from reactive species to other molecules in plasma .…”

Afterglow corona discharge air plasma (ACDAP) for inactivation of common food-borne pathogens

“…Nitrogen and oxygen are the major constituents of air. It has been reported that fast etching action on cell membrane by electrons, ions and radicals are primary reasons of oxygen and nitrogen plasma inactivation, which leads to the cellular contents effuse and engender bacteria death (Zhang & Chen, 2009). Also, an electrostatic mechanism may potentially contribute to biological effects of corona discharges (Timoshkin et al, 2012).…”