Lassen Klaus S, Nordby Bolette, Grün Reinar
The National Centre for Hospital Hygiene (CAS), Statens Serum Institut, Copenhagen S, Denmark.
J Biomed Mater Res B Appl Biomater. 2005 Jul;74(1):553-9. doi: 10.1002/jbm.b.30239.
The sporicidal effect of 20 different radio-frequency plasma processes produced by combining five different gas mixtures [O(2), Ar/H(2) (50/50%), Ar/H(2) (5/95%), O(2)/H(2) (50/50%), O(2)/H(2) (95/5%)] with four power/pressure settings were tested. Sporicidal effects of oxygen-containing plasmas were dependent on power at low pressure settings but not at high pressure settings. In the absence of oxygen no power dependency was observed at either high or low pressure settings. Survivor curves obtained with the use of nonoxygen plasmas typically had a tailing tendency. Only a mixture-optimized Ar/H(2) (15/85%) plasma process was not encumbered by tailing, and produced a decimal reduction time (D value) below 2 min for Bacillus stearothermophilus spores. Scanning electron microscopy showed that a CF(4)/O(2) plasma did more damage to the substrate than the 15/85% Ar/H(2) plasma. The present results indicate that UV irradiation inactivation is swift and power and pressure independent. Additionally, it is produced at low energy. However, it is not complete. Inactivation through etching is highly power and pressure dependent; finally, inactivation by photodesorption is moderately power and pressure dependent. A sterilization process relying on this mechanism is very advantageous because it combines a highly sporicidal effect with low substrate damage.
测试了通过将五种不同的气体混合物[O₂、Ar/H₂（50/50%）、Ar/H₂（5/95%）、O₂/H₂（50/50%）、O₂/H₂（95/5%）]与四种功率/压力设置相结合产生的20种不同射频等离子体过程的杀孢子效果。含氧化合物等离子体的杀孢子效果在低压设置下取决于功率，但在高压设置下则不然。在没有氧气的情况下，在高压或低压设置下均未观察到功率依赖性。使用非氧等离子体获得的存活曲线通常具有拖尾趋势。只有经过混合优化的Ar/H₂（15/85%）等离子体过程没有拖尾现象，并且对嗜热脂肪芽孢杆菌孢子产生的十进制减少时间（D值）低于2分钟。扫描电子显微镜显示，CF₄/O₂等离子体对底物的损伤比15/85% Ar/H₂等离子体更大。目前的结果表明，紫外线照射灭活迅速且与功率和压力无关。此外，它是在低能量下产生的。然而，它并不彻底。通过蚀刻进行的灭活高度依赖于功率和压力；最后，通过光解吸进行的灭活适度依赖于功率和压力。基于这种机制的灭菌过程非常有利，因为它结合了高度的杀孢子效果和对底物的低损伤。
