Safety aspects of atmospheric pressure helium plasma jet operation on skin: In vivo study on mouse skin

Abstract

Biomedical applications of plasma require its efficacy for specific purposes and equally importantly its safety. Herein the safety aspects of cold plasma created with simple atmospheric pressure plasma jet produced with helium gas and electrode discharge are evaluated in skin damage on mouse, at different duration of exposure and gas flow rates. The extent of skin damage and treatments are systematically evaluated using stereomicroscope, labelling with fluorescent dyes, histology, infrared imaging and optical emission spectroscopy. The analyses reveal early and late skin damages as a consequence of plasma treatment, and are attributed to direct and indirect effects of plasma. The results indicate that direct skin damage progresses with longer treatment time and increasing gas flow rates which reflect changes in plasma properties. With increasing flow rates, the temperature on treated skin grows and the RONS formation rises. The direct effects were plasma treatment dependent, whereas the disclosed late—secondary effects were more independent on discharge parameters and related to diffusion of RONS species. Thermal effects and skin heating are related to plasma-coupling properties and are separated from the effects of other RONS. It is demonstrated that cumulative topical treatment with helium plasma jet could lead to skin damage. How these damages can be mitigated is discussed in order to provide guidance, when using atmospheric pressure plasma jets for skin treatments.

Comparison of Direct and Indirect cold atmospheric-pressure plasma methods in the B16F10 melanoma cancer cells treatment

“…Also, mouse skin temperature was evaluated in-vivo experiment and temperature increase was reported about 1 ± 0.3 ° c , showing that this change in temperature cannot inflict any thermal damages. In this regard, the result of H&E staining after plasma exposure proves that cold plasma doesn’t cause any thermal damages 73 .…”

Long-Term Risk Assessment for Medical Application of Cold Atmospheric Pressure Plasma

“…In addition to in vitro research, plasma-associated side effects and risk potential were also evaluated in animal experiments. Kos et al [40] investigated direct and indirect damage mechanisms in a mouse model and concluded that plasma application (jet system) is not as safe as described by numerous other authors. However, critical analysis of this study shows various limitations.…”

A Novel Micro Cold Atmospheric Plasma Device for Glioblastoma Both In Vitro and In Vivo

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