Abstract: The authors carried out the reactive species and sterilization efficacy of a direct current atmospheric pressure Ar+O₂ (2%) cold plasma micro jet. Electron spin resonance (ESR) spectroscopy and other methods were employed to investigate the reactive species of the plasma. The plasma micro jet was submerged in Staphyloccocus aureus suspensions for the study of its sterilization effects. Two types of reactive species produced in the solution were monitored by ESR spectroscopy directivity, namely hydroxyl radical (OH?) and singlet oxygen (¹O₂). Superoxide anion radical (O₂^-?) was also proved in the system directly. O₃ and H₂O₂ in the system were also analysed quantitatively. With 10 min Ar+O₂(2%) cold plasma micro jet treatment, a quick increase of the percent inactivation from 0 to 99.9% was achieved. Non-thermal atmospheric pressure microplasma micro jet can generate enormous reactive species and can efficiently inactivate S. aureus in water. The possible mechanism is that the reactive species induced the cell generate superoxide membrane lipid, protein and DNA through various oxidation progress. Non-thermal atmospheric pressure plasma micro jet has enormous potential clinical application.

Key words: atmospheric pressure cold plasma, reactive oxygen species, Staphyloccocus aureus

摘要： 系统分析了以Ar+O₂ (2%)为气源, 以直流辉光放电方式激发的大气压低温等离子体中的活性氧(ROS)成分及其杀菌的生物学效应。采用电子自旋共振(ESR)等技术方法, 对等离子体的ROS成分进行了检测分析, 同时采用低温等离子体在水下作用的方式探究了其对金黄色葡萄球菌的杀灭作用。通过电子自旋共振分析, 直接检测出两种活性氧自由基, 分别是羟自由基(OH?)和单线态氧(¹O₂), 间接证明了超氧阴离子(O₂^-?)的存在。同时用臭氧检测仪等对O₃和H₂O₂等进行了定量分析。等离子体能有效杀灭金黄色葡萄球菌, 10分钟杀菌率能达到99.9%。 低温等离子体中含有大量的ROS成分, 并能有效杀灭金黄色葡萄球菌, 可能的杀菌机制是ROS成分诱导细菌细胞内脂质、蛋白质、DNA等过氧化。研究结果提示大气压低温等离子体在临床医学研究中具有潜在的巨大应用价值。

关键词: 大气压低温等离子体, 活性氧, 金黄色葡萄球菌