Study of Atmospheric Microplasma for Plasma-Life Science

Abstract

Atmospheric microplasma has been intensively studied for various application fields, since this technology has features shown here: generated around only 1 kV under atmospheric pressure, discharge gap of only 10 to 100 μm, dielectric barrier discharge. Low discharge voltage atmospheric plasma process is an economical and effective solution for various applications such as indoor air control including sterilization, odor removal, surface treatment, and would be suitable for plasma-life science field such as medical application.In this paper, the basic study for plasma-life science will be presented. One life science application of microplasma is "sterilization". The sterilization process was carried out with active species generated between the microplasma electrodes. The active species were observed by emission spectrometry. The spectra showed the existence of active species, and the microplasma had typical characteristics of non-thermal plasma. Sterilization of E. coli was confirmed after microplasma treatment with Ar gas. The bacteria shape was changed after the microplasma process . The other application is "Surface treatment" by long life active species of materials which used for the medical field. The targets are glass, polymer film and others could be also possible.The process is known as remote microplasma sterilization method. Microplasma generated by both air and Ar are effective for sterilization. Observation by the SEM images shows the E. coli had a shrunked shape after the microplasma treatment. The contact angle of a water droplet on the polymer surface was measured to estimate its hydrophilicity. The relation between the contact angle and treatment time was investigated. Contact angle decreased from 75.6° to 45.6° after 10 s of treatment.

Basic study on indoor air quality improvement by atmospheric plasma

“…that can decompose harmful substances [16,17]. During plasma processes also NOx and O 3 are generated [18,19]. This time, O 3 was measured as one of harmful materials.…”