Portal de Periódicos da CAPES

Cold Atmospheric Air Plasma Sterilization against Spores and Other Microorganisms of Clinical Interest

2012; American Society for Microbiology; Volume: 78; Issue: 15 Linguagem: Inglês

10.1128/aem.00583-12

1098-5336

Tobias G. Klämpfl, Georg Isbary, Tetsuji Shimizu, Yang‐Fang Li, Julia Zimmermann, Wilhelm Stolz, Jürgen Schlegel, G. E. Morfill, Hans-Ulrich Schmidt,

Inhalation and Respiratory Drug Delivery

ABSTRACT Physical cold atmospheric surface microdischarge (SMD) plasma operating in ambient air has promising properties for the sterilization of sensitive medical devices where conventional methods are not applicable. Furthermore, SMD plasma could revolutionize the field of disinfection at health care facilities. The antimicrobial effects on Gram-negative and Gram-positive bacteria of clinical relevance, as well as the fungus Candida albicans , were tested. Thirty seconds of plasma treatment led to a 4 to 6 log 10 CFU reduction on agar plates. C. albicans was the hardest to inactivate. The sterilizing effect on standard bioindicators (bacterial endospores) was evaluated on dry test specimens that were wrapped in Tyvek coupons. The experimental D 23 ° C values for Bacillus subtilis , Bacillus pumilus , Bacillus atrophaeus , and Geobacillus stearothermophilus were determined as 0.3 min, 0.5 min, 0.6 min, and 0.9 min, respectively. These decimal reduction times ( D values) are distinctly lower than D values obtained with other reference methods. Importantly, the high inactivation rate was independent of the material of the test specimen. Possible inactivation mechanisms for relevant microorganisms are briefly discussed, emphasizing the important role of neutral reactive plasma species and pointing to recent diagnostic methods that will contribute to a better understanding of the strong biocidal effect of SMD air plasma.