One of the most desired aims in plasma medicine is to inactivate prokaryotic cells and leave eukaryotic cells unharmed or even stimulate proliferation to promote wound healing. The method of choice is to precisely control the plasma component composition. Here the authors investigate the inactivation of bacteria ( Escherichia coli ) by a plasma jet treatment. The reactive species composition created by the plasma in liquids is tuned by the use of a shielding gas device to achieve a reactive nitrogen species dominated condition or a reactive oxygen species dominated condition. A strong correlation between composition of the reactive components and the inactivation of the bacteria is observed. The authors compare the results to earlier investigations on eukaryotic cells and show that it is possible to find a plasma composition where bacterial inactivation is strongest and adverse effects on eukaryotic cells are minimized.
Authors are grateful Steffen Hahn for assistance with the liquid diagnostic and the microbial tests. The work was funded by the BMBF (Grant Nos.: 03Z2DN11 and 12) as well as project “Plasmamedical Research—New pharmaceutical and medical fields of application” funded by the Ministry of Education, Science and Culture of the State of Mecklenburg-Western Pomerania and the European Union, European Social Fund (Grant No.: AU 11 038; ESF/IV-BM-B35-0010/13).
I. INTRODUCTION II. MATERIAL AND METHODS A. Plasma jet and gas curtain B. Molecular beam mass spectrometry C. Nitrite and nitrate, pH and hydrogen peroxide D. Inactivation of bacteria III. RESULTS A. Molecular beam mass spectrometry B. pH, hydrogen peroxide, nitrite, and nitrate C. Inactivation of bacteria IV. DISCUSSION V. CONCLUSION