The Physical Effects of Plasma Medicine on Cells: Radio Frequency Stimulated Intercellular and Intracellular Mechanical Waves

In the last decade of research works upon plasma medicine using cold atmospheric plasmas (CAP), reactive oxygen and nitrogen species (RONS) are believed to be the major role of these applications. This thus raises the indirect treatments that use the plasma-treated solutions or drugs rather than treat the targeting cells or tissues directly with CAP. However, the difference between direct and indirect treatments cannot be ignored. The indirect treatment does not include the electromagnetic (EM) radiation from CAP. The latter is thus named as the physical effects of plasma medicine. Due to the surface charge on the cell membrane, the membrane oscillation under the external electric field has been reported. In this work, we developed a Michelson laser interferometer system coupled with a high-speed ICCD camera and a radio frequency (RF) emission system to capture the cell membrane and the propagation of the resulting mechanical waves. The system can observe such an oscillation in 3D and real-time. In the further analysis, we will discuss the propagation of such an oscillation, mainly a transverse wave along the cell membrane from the center to its pseudopodia, and the wave in the extracellular medium. The corresponding cancer cell viability and sensitization to cancer medicines are also analyzed. The physical effects of species transportations on the cell membrane are thus suggested.