Study on the killing effect of cold atmospheric pressure plasma on MRSA Staphylococcus aureus in vitro and in vivo infection model

Aims: Non-thermal atmospheric-pressure plasma (cold plasma), is described as a partly ionized gas. Cold plasma is a new method of medicine for killing the bacteria, treatment of cancer diseases, accelerates the healing of infectious ulcers, especially in infection caused by Meticillin-resistant Staphylococcus aureus (MRSA). This study aimed to investigate the impact of Non-thermal atmospheric-pressure plasma on MRSA S. aureus organism isolated from burn wound infection in vitro and in vivo. Methodology and results: Five MRSA S. aureus strains were recovered in burn patients from Shahid Motahari Burns Hospital, Tehran, Iran. They confirmed by microbiology and biochemical tests. Antibiotic susceptibility testing was performed using Kirby Bauer Disk Diffusion Method with selected antibiotics. Then, the antibacterial impact of atmospheric non-thermal plasma on MRSA in vitro and in vivo at different times was assessed. After that, the tissue was randomly separated from control and treated mice with plasma and transferred to the Histopathology Laboratory for further evaluation. Results of the inactivation of MRSA by non-thermal atmospheric plasma showed no bacterial growth. Also, results of the impact of non-thermal helium plasma in vivo environment revealed that, in addition to healing in the animal wound, the burn wounds infection was healed and treated according to the histological results. Conclusion, significance and impact of study: Our results confirmed the inactivation of MRSA S. aureus, healing of animal burn wound and complete treatment by non-thermal atmospheric plasma. It recommended that cold plasma can be used for the treatment of burn wounds infection due to the gentle on the human skin. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.