2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 201524aC-1
September 24th (Thu.), <10:00-12:00>
Room 3Analysis of bacterium isolated from used soluble cutting oil
and it’s tolerance toward pulsed-discharge plasma treatment
Makoto HIROSAWA, Takanori TANINO, Kouhei MAKITA, Takayuki OHSHIMA
Graduated School of Science and Technology, Gunma University

Abstract:
In this study, we focused on a bacterium that was isolated from usedsoluble cutting oil after pulsed-discharge plasma treatment. A bacteria
identification analysis based on the 16s rRNA coding sequence region
concluded that the bacterium is Bacillus barbaricus with 98.30% homology.
Isolated B. barbaricus was cultivated both in liquid medium for 4, 22 h and on
agar plate for 1 week. The former condition could allow B. barbaricus to bevegetative cell form and the later condition could allow it to form spore. All cells
showed tolerance toward puled-discharge plasma inactivation treatment indistilled water. We also investigated tolerances of B. barbaricus toward heat andozone inactivation treatments. Contrary to our expectations, it didn’t show
significant tolerances toward heat and ozone. From these results, B. barbaricus
possesses only significant tolerance toward pulsed-discharge plasma
inactivation treatment.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

24aC-2September 24th (Thu.), <10:00-12:00>
Room 3The effect of gas flow rate and composition in nanosecond
pulsed plasma irradiation on mouse melanoma cell
○Yuki Shirakawa*, Kazue Mizuno** and Ryo Ono*
*Department of Advanced Energy, The University of Tokyo, ** Department ofMaterials Engineering, The University of Tokyo

Abstract:
The relation between survival rate of mouse melanoma cell treated withnanosecond pulsed streamer discharge and gas flow rate and composition areinvestigated. Using N2, low gas flow rate induces more cell death. Using N2/O2
mixed gas, O2 concentration has little effect on cell survival rate. The results
imply that in our experiment condition some reactive species derived from water
vapor such as OH are more effective for mouse melanoma cell death thanreactive species derived from O2 such as O and NO.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

24aC-3September 24th (Thu.), <10:00-12:00>
Room 3Fundamental study of a novel gene transfection of
mammalian cells by water-in-oil droplet manipulation in anelectric fieldYasuhiro TAKAO
Department of Environmental and Life Sciences, Toyohashi University ofTechnology

Abstract:
We developed a novel gene transfection method, water-in-oil (W/O)
droplet electroporation, using dielectric oil and a liquid droplet containing living
cells and transgene DNA. This method is based on water-in-oil droplet
manipulation by using electrostatic force. When a water droplet is placed
between a pair of electrodes, a reciprocal motion is made by applying a DC
electric field. This droplet motion is brought about as follows. First, a droplet iscarried to one electrode by Coulomb force, possibly due to electrostaticinduction. When the droplet makes contact with the electrode, droplet is charged
with the same polarity as the electrode. The droplet then moves to the otherelectrode and the same process occurs repeatedly. Furthermore, more intenseelectric field can induce droplet deformation and it leads instantaneous shortcircuit via the droplet. Small holes could be made in the cell membrane during
the short circuit, and genes could be introduced into the cells. We haveinvestigated a gene transfection using the droplet containing mammalian culture
cells (HEK293 cell) and foreign plasmid DNA. Viability and transfection levelmeasured 24 hours after the voltage application under various applied condition
were investigated.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

24aC-4September 24th (Thu.), <10:00-12:00>
Room 3

Plasma Irradiation to Subcutaneous Cancer Tumor on Miceand Verification of Immune System○Kenta YONETAMARI*, Yuki SHIRAKAWA*, Kazue MIZUNO** and Ryo ONO*
*Department of Advanced Energy, The University of Tokyo,**Department ofBioengineering, The University of Tokyo

Abstract:
Cancer treatment using plasma has intensively studied these days. In
this study, mouse melanoma cells were injected subcutan eously on mice andtreated using nanosecond pulsed streamer discharge. Two types of mice wereused, CD2F1 and Balb/c nu/nu.
The former has immunity and the latter lacks immunity. It was shown thatthe treatment of CD2F1 is effective, while that of Balb/c nu/nu is not effective. It
suggests that the plasma treatment might stimulate the immune system in micethat is effec tive for cancer treatment.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

24aC-5September 24th (Thu.), <10:00-12:00>
Room 3

Verification of Sterilization Effect by OH radicals Using
Vacuum Ultraviolet Light Method○Kenta YONETAMARI and Ryo ONO
The University of Tokyo

Abstract:
Recently, plasma medicine is one of the most attracting fields becauseradicals in plasma have the therapeutic and sterilization effects. However, themechanism is not revealed so plasma medicine is not yet to use. In this study,sterilization experiment of bacillus atrophaeus (ATCC9372) was performed using
VUV method which is developed in our previous work. As a result, sterilization
effect was observed when wet He and He/O2 was used as the working gas. This
result indicates that OH radical kills bacteria.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

24aC-6
September 24th (Thu.), <10:00-12:00>
Room 3

Examination of Cell Separation Condition Using the Inclined
Comb-shaped Dielectrophoretic Electrodes○Masayo TAKANO, Takayuki ITOI, Takaharu ENJOJI and Yoshikazu
WAKIZAKAAFI Corporation

Abstract:
The importance of cell separation techniques are increasing with
development of biopharmaceutical and regenerative medicine. Dielectrophoresis(DEP) is a noninvasive method for cell separation without labeling the cells. We
had developed the DEP devices with the inclined comb-shaped electrodes forcell separation, and examined the effect of micro-gap size between electrodes,
flow rate and AC voltage on cell separation efficiency. Furthermore, the viable
and the non-viable cells were separated, and also one cell line was separated
from mixture of two cell lines by the DEP device.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

24aC-7
September 24th (Thu.), <10:00-12:00>
Room 3

Study of dielectrophoretic property of DNA-labeled dielectric
microbeads for DNA detection
Michihiko Nakano, Hiromichi Kasahara, Zhenhao Ding, ○Junya Suehiro
Department of Electrical Engineering, Kyushu UniversityAbstract:
New DNA detection method using dielectrophoresis (DEP) of dielectric
microbeads was proposed. The method is based on dynamic change ofmicrobeads DEP by attaching DNA. Dielectric microbeads having natively
negative DEP property become behaving positive DEP when they are labeledwith DNA. The DNA-labeled microbeads can be collected on a microelectrode bypositive DEP. DEP collection of the DNA-labeled microbeads causes theimpedance change of the microelectrode. By measuring the impedance change,DNA-labeled microbeads are detected. The aim of this study is to investigate
influence of DNA on the dielectrophoretic property of the dielectric microbeads.
The crossover frequency of DEP and zeta potential of the microbeads wereinvestigated. Three kinds of DNA and two kinds of microbeads were used. From
the results, it was suggested that not only the conductance of DNA but also
permittivity of DNA could affect DEP of the microbeads. Moreover, it isdemonstrated that quantitative detection of DNA.