Plasma disinfection and sterilization
Plasmas reduce concentrations of pathogens upon contact with contaminated surfaces. Plasma destroys bacteria, viruses, fungi and prions; it also removes toxins and further organic contaminants. Even complete sterilization is possible with prolonged exposure to the plasma. Most importantly, strong disinfection can be achieved with atmospheric pressure air plasmas, produced by a piezoelectric direct discharge (PDD). Thus, plasma disinfection does not require expensive vacuum equipment or toxic chemicals, making the process cheap and environmentally friendly. Atmospheric pressure plasmas of PDD discharge is cold, making the plasma disinfection very gentle comparing to the standard disinfection procedures using pressurized hot air, pressurized hot water vapor or toxic substances. It affects only a very thin surface layer. Because of this, plasmas can disinfect a variety of sensitive surfaces, including living tissues and even open wounds.
Plasma disinfection mechanisms
Upon contact with the treated surface, the chemically active cold atmospheric plasma initiates a multitude of physical and chemical processes. The main sterilization process is decomposition of organic molecules of living organisms by bombardment with electrons, ions and short-lived neutral chemical species. The ion bombardment breaks hydrogen bonds of organic molecules. Further, short-lived reactive chemical species oxidize organic molecules. These processes produce lighter and volatile organic molecules, which evaporate from the surface, leaving it not only disinfected, but also in the ultra-fine clean state.
|