The Efficiency of the Cold Argon-oxygen Plasma jet to reduce Escherichia coli and Streptococcus pyogenes from solid and liquid ambient

Bacterial infections in hospitals can be consider as a damaging factor in laboratory environment (healthcare setting) since the rate of antibiotic-resistant bacteria is increasing overtime. Therefore, finding an effective and rapid method is essential for sterilization. The aim of this study was efficiency of cold argon-oxygen plasma used for sterilization of the Escherichia coli and Streptococcus pyogenes in liquid and solid media.
Non-thermal single argon-oxygen plasma jet was produced by high sinusoidal voltage (18.56 kHZ). Then 3*108 CFU/ml of E. coli and 3*107 CFU/ml of S. pyogenes were inoculated in LB (Luria-Bertani) liquid and solid media, separately. These inoculated media were treated with plasma for different time periods. Results were measured by turbidity test in liquid media and measuring clear zone in solid media. Moreover pieces present in the plasma and concentration of zone were measured.
The results suggested that cold argon/oxygen plasma jet including atomic and molecular species, has a high efficiency to destroy gram-positive and gram-negative bacteria at short time in a liquid medium (less than 15 minutes) and solid (less than 30 second). Also, results have shown that the influence factor of gram-negative bacteria (E. coli) was more than gram-positive bacteria (S. pyogenes).
Since many of sterilization procedures including chemical and physical methods or wet and dry heat sterilization in solid or liquid ambient have faced to functional limitations; according to the results of this study, this new technology is a powerful tool for disinfection of surfaces in hospitals and public places.