Atmospheric pressure plasma jet-mouse skin interaction: Mitigation of damages by liquid interface and gas flow control

Abstract

The possible benefits of an atmospheric pressure plasma jet skin treatment have been tested in vivo on mouse skin. Many studies have been conducted in vitro on mouse skin cells, but only a few in vivo where, due to the complexity of the biological system, plasma can cause severe damages. For this reason, we investigated how kHz plasma generated in a jet that is known to inflict skin damage interacts with mouse skin and explored how we can reduce the skin damage. First, the focus was on exploring plasma effects on skin damage formation with different plasma gases and jet inclinations. The results pointed to the perpendicular orientation of a He plasma jet as the most promising condition with the least skin damage. Then, the skin damage caused by a He plasma jet was explored, focusing on damage mitigation with different liquid interfaces applied to the treatment site, adding N2 to the gas mixture, or alternating the gas flow dynamics by elongating the jet's glass orifice with a funnel. All these mitigations proved highly efficient, but the utmost benefits for skin damage reduction were connected to skin temperature reduction, the reduction in reactive oxygen species (ROS), and the increase in reactive nitrogen species (RNS).

The state-of-the-art of atmospheric pressure plasma for transdermal drug delivery

“…Therefore, they suggested that the electromagnetic radiation from the plasma could have a biological effect on cells. Additionally, Wu et al [125] once measured the magnetic field generated by the plasma jet using a magnetic field probe with a bandwidth ranging from 0.1 MHz to 1 GHz and found that the peak magnetic field produced by the plasma jet was approximately 0.05 dBm.…”

Plasma for nitrogen fixation by using N2/O2 mixture: Reaction pathway, energy flow, and plasma reactor

“…In fact, natural lightning processes contribute a substantial portion to global NF. Moreover, research on air plasma is related to various subjects such as atmospheric chemistry, [34] reentry heating of space vehicles, [35] surface treatment of materials, [36] plasma medicine, [37][38][39][40][41][42][43][44][45][46][47][48] and other plasma technologies. [49,50] In short, this paper will mainly focus on the progress of plasma NF using N 2 /O 2 mixture or dry air as the working gas.…”

“…In fact, natural lightning processes contribute a substantial portion to global NF. Moreover, research on air plasma is related to various subjects such as atmospheric chemistry, [ 34 ] re‐entry heating of space vehicles, [ 35 ] surface treatment of materials, [ 36 ] plasma medicine, [ 37–48 ] and other plasma technologies. [ 49,50 ]…”

Instant switching control between two types of plasma-driven liquid flows

“…Figures 5(a) and 5(b) show the emission spectra in the 300-440 nm (exposure time = 1000 ms) and the 700-840 nm (exposure time = 20 ms) wavelength ranges, respectively.The emission spectra were minor in the 440-700 nm wavelength range. In experimental results suggesting that an unusual spectral change has an important effect on the change in liquid flows, the emission spectra were dominated by excited OH (309 nm), excited molecular N 2 (315-380 nm, 2nd positive system), and excited atomic Ar (around 420 nm, 700-840 nm) [27][28][29][30][31][32]. As the frequency increased from 4 to 10 kHz, the emission intensities of excited OH and excited molecular N 2 decreased while those of excited atomic Ar increased.…”

“…In experimental results suggesting that an unusual spectral change has an important effect on the change in liquid flows, the emission spectra were dominated by excited OH (309 nm), excited molecular N 2 (315-380 nm, 2nd positive system), and excited atomic Ar (around 420 nm, 700-840 nm). [27][28][29][30][31][32] As the frequency increased from 4 to 10 kHz, the emission intensities of excited OH and excited molecular N 2 decreased while those of excited atomic Ar increased. Therefore, the plasma-driven liquid flows can be controlled by adjusting the active species supplied to the liquid surface.…”