Abstract
A plasma source using a coaxial cable for microwave transmission type has advantages such as portability, simple configuration, and ability to operate at atmospheric pressure. Using this plasma source, we clarified its sterilization efficacy against Geobacillus stearothermophilus. A log reduction number of G. stearothermophilus of at least 5 (10^<-5>) was obtained under conditions of a gas flow rate of argon of 14l/min, input power of 400W and sterilization temperature of 353K. It is possible to sterilize Escherichia coli on plasma exposure temperature of 383K although the heated argon gas can't sterilize at same exposure temperature of the plasma flow. The sterilization mechanism of plasma flow was clarified by observing a shape variation analysis of SEM and the potassium leakage of the ICP-MS method.
