Atmospheric plasma jet array in parallel electric and gas flow fields for three-dimensional surface treatment

Using the Taguchi method to narrow experimental parameters, the antimicrobial efficiency of a cold atmospheric plasma jet (CAPJ) treatment was investigated. An L9 array with four parameters of CAPJ treatments, including the application voltage, CAPJ-sample distance, argon (Ar) gas flow rate, and CAPJ treatment time, were applied to examine the antimicrobial activity against Escherichia coli (E. coli). CAPJ treatment time was found to be the most influential parameter in its antimicrobial ability by evaluation of signal to noise ratios and analysis of variance. 100% bactericidal activity was achieved under the optimal bactericidal activity parameters including the application voltage of 8.5 kV, CAPJ-sample distance of 10 mm, Ar gas flow rate of 500 sccm, and CAPJ treatment time of 300 s, which confirms the efficacy of the Taguchi method in this design. In terms of the mechanism of CAPJ’s antimicrobial ability, the intensity of hydroxyl radical produced by CAPJ positively correlated to its antimicrobial efficiency. The CAPJ antimicrobial efficiency was further evaluated by both DNA double-strand breaks analysis and scanning electron microscopy examination of CAPJ treated bacteria. CAPJ destroyed the cell wall of E. coli and further damaged its DNA structure, thus leading to successful killing of bacteria. This study suggests that optimal conditions of CPAJ can provide effective antimicrobial activity and may be grounds for a novel approach for eradicating bacterial infections.

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Three-Dimensional Simulation of Plasma Spray Jet

Heat Transfer: Volume 3 ◽

10.1115/ht2003-47153 ◽

2003 ◽

Cited By ~ 2

Author(s):

H. Xiong ◽

L. L. Zheng ◽

S. Sampath ◽

Jim Fincke ◽

Richard Williamson

Keyword(s):

Plasma Spray ◽

Gas Flow ◽

Probability Distributions ◽

Three Dimensional ◽

Plasma Jet ◽

Carrier Gas ◽

Spray Process ◽

Lagrangian Coordinate ◽

Dimensional Simulation ◽

Physical Phenomena

A three-dimensional computational model has been developed to describe the compressible, multi-component, turbulent, reacting plasma jet coupled with the orthogonal injection of carrier gas and particles. This model has been applied to plasma spray process that includes physical phenomena such as heating, melting, accelerating, and evaporation of in-flight particles. The entrained particles, NiCrAlY and ZrO2, are discretely treated in a Lagrangian coordinate and stochastically generated by sampling from the probability distributions of the particle size and its velocity at the injection nozzle. In this study, special attention has been directed to the effects of carrier gas injection on the characteristics of plasma jet. The computational results show that the injection of carrier gas from the orthogonal injector above the plasma jet introduce the 3-D phenomena of plasma gas flow. The plasma jet is defected and the thermo-fluid flow near the injector is locally deformed.

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Strong discharge processes by atmospheric plasma jet array without external ground electrode

2015 IEEE International Conference on Plasma Sciences (ICOPS) ◽

10.1109/plasma.2015.7179600 ◽

2015 ◽

Author(s):

Jae Young Kim ◽

Sun Young Lee ◽

Mihyang Shin ◽

Dae Won Moon ◽

Heung-Sik Tae

Keyword(s):

Plasma Jet ◽

Atmospheric Plasma ◽

Jet Array

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Titanium alloy surface treatment using an atmospheric plasma jet in nitrogen pulsed discharge conditions

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2007.01.045 ◽

2007 ◽

Vol 201 (16-17) ◽

pp. 7292-7302 ◽

Cited By ~ 23

Author(s):

E. Panousis ◽

F. Clément ◽

J.-F. Loiseau ◽

N. Spyrou ◽

B. Held ◽

...

Keyword(s):

Titanium Alloy ◽

Surface Treatment ◽

Plasma Jet ◽

Atmospheric Plasma ◽

Alloy Surface ◽

Pulsed Discharge

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Interaction of Cold Atmospheric Argon and Helium Plasma Jets with Bio-Target with Grounded Substrate Beneath

Applied Sciences ◽

10.3390/app9214528 ◽

2019 ◽

Vol 9 (21) ◽

pp. 4528 ◽

Cited By ~ 7

Author(s):

Irina Schweigert ◽

Dmitry Zakrevsky ◽

Pavel Gugin ◽

Elena Yelak ◽

Ekaterina Golubitskaya ◽

...

Keyword(s):

Cancer Cells ◽

Gas Flow ◽

Fluid Model ◽

Plasma Jet ◽

Plasma Jets ◽

Atmospheric Plasma ◽

Maximum Efficiency ◽

Embryonic Cells ◽

Plasma Parameters

The cold atmospheric pressure plasma jet interaction with the bio-target is studied in the plasma experiment, 2D fluid model simulations, and with MTT and iCELLigence assays of the viability of cancer cells. It is shown, for the first time, that the use of the grounded substrate under the media with cells considerably amplifies the effect of plasma cancer cell treatment in vitro. Plasma devices with cylindrical and plane geometries generating cold atmospheric plasma jets are developed and tested. The sequence of the streamers which forms the plasma jet is initiated with a voltage of 2.5–6.5 kV applied with the frequency 40 kHz. We suggest using the grounded substrate under the bio-target during the plasma jet treatment of cancer cells. The analysis of the measured plasma spectra and comparison of OH-line intensity for different voltages and gas flow rates allows us to find a range of optimal plasma parameters for the enhanced OH generation. The time-dependent viability is measured for human cell lines, A431 (skin carcinoma), HEK 293 (kidney embryonic cells), and A549 (human lung adenocarcinoma cells) after the plasma jet treatment. The results with cell-based experiments (direct treatment) performed with various plasma jet parameters confirm the maximum efficiency of the treatment with the optimal plasma parameters.

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