Slit shaped microwave induced atmospheric pressure plasma based on a parallel plate transmission line resonator

Abstract

A new type of microwave-excited atmospheric pressure plasma source, based on the principle of parallel plate transmission line resonator, is developed for the treatment of large areas in biomedical applications such as skin treatment and wound healing. A stable plasma of 20 mm width is sustained by a small microwave power source operated at a frequency of 700 MHz and a gas flow rate of 0.9 slm. Plasma impedance and plasma density of this plasma source are estimated by fitting the calculated reflection coefficient to the measured one. The estimated plasma impedance shows a decreasing trend while estimated plasma density shows an increasing trend with the increase in the input power. Plasma uniformity is confirmed by temperature and optical emission distribution measurements. Plasma temperature is sustained at less than 40 °C and abundant amounts of reactive species, which are important agents for bacteria inactivation, are detected over the entire plasma region. Large area treatment ability of this newly developed device is verified through bacteria inactivation experiment using E. coli. Sterilization experiment shows a large bacterial killing mark of 25 mm for a plasma treatment time of 10 s.

How plasma induced oxidation, oxygenation, and de-oxygenation influences viability of skin cells

“…Skin cells were chosen because of the intense interest in the plasma stimulation of skin cells to aid in the healing of chronic wounds. 23,[37][38][39][40][41] Cells were cultured in Dulbecco modified Eagle's medium (DMEM) supplemented with 10% (v/v) fetal bovine serum, 100 IU ml À1 penicillin, and 100 lg ml À1 streptomycin at 37 C under a humidified atmosphere of 5% CO 2 . A total of 5000 cells suspended in 200 ll of cell culture medium was added to 96well tissue culture polystyrene plates and incubated for 24 h prior to treatments.…”

Self-consistent fluid modeling and simulation on a pulsed microwave atmospheric-pressure argon plasma jet

“…With a Guass type pulsed microwave power function as shown in Eq. (21), the spatio-temporal distributions of the electron density, the electron temperature, the electric field, and the absorbed power density have been simulated with the time increment of 1 ls during the time span from 1 ls to 100 ls. The simulation results suggest that the peaks values of the electron temperature and the electric field are consistent with the input pulsed microwave power, while the peaks values of the electron density and the absorbed power density are lagged to the input pulsed microwave power.…”

“…In many time steps, the input microwave power approximates zero for Gauss function of Eq. (21). In our simulation, zero power input will induce the converged difficulty; thence, we add 1 mW power to make sure the simulation smoothly, as shown in Eq.…”

“…In our simulation, zero power input will induce the converged difficulty; thence, we add 1 mW power to make sure the simulation smoothly, as shown in Eq. (21).…”

“…17 To pay attention on microwave-driven plasma devices, many researches have focused on optimizing the device structure, in order to acquire special plasma composition, plasma size, and more efficient energy absorbed by plasmas. [18][19][20][21][22] Our previous works have proposed some types of microwave-driven plasma devices excited by surface waves of surface plasmon polaritons (SPPs). [23][24][25][26][27][28] At the interface between a metal (or overdense plasma) and a dielectric material, the surface wave of SPPs is excited as a special electromagnetic (EM) wave.…”