Investigating the Effects of Cold Plasma on Cancer Cell Migration in the Presence of a Static Magnetic Field

Abstract

Cold plasma is used in a wide range of applications [1]–[3] One of the primary uses of plasma is in the field of medicine. Moreover, many techniques have been suggested to enhance plasma performance, among which the inclusion of an external static magnetic field is one [4], [5]. This paper used a low-power (20-watt) RF 13.56 MHz plasma to investigate the effect of cold plasma on cancer cells' migration rate in the presence of a static magnetic field. The result of the scratch healing assay is shown in Figure 1 (Ⅰ and Ⅱ). The results are evaluated after 24 hours. Figure 1 (Ⅰ-A) is before plasma treatment (control), (Ⅰ-B) is without treatment, (Ⅰ-C) is 15 seconds of plasma treatment, and (Ⅰ-D) is plasma and SMF treatment. The area of free space in the created gap has been evaluated by image processing software. The percentage of free space compared to the total space is specified in the diagram (Figure1-Ⅱ). As shown in the figure, the empty space for the state where the plasma is combined with the magnetic field is twice the state of the plasma alone. One of the main components of plasma that changes the presence of a magnetic field is the density and temperature of electrons in cold plasma. The electron temperature was evaluated based on the Boltzmann plot method, and the electron density measurement was calculated using the Saha-Boltzmann equation (figure 1-Ⅲ). The Boltzmann diagram is drawn using the used plasma spectrum, which was used in the previous work [6]. The calculation indicates that the electron temperature Te and electron density ne is estimated as 1.04 eV and for the absence of SMF, and 1.24 eV and for the presence of SMF, respectively Although several factors are involved in the effect of plasma, in this work, the temperature and electron density of the plasma were evaluated. Because apart from the direct impact on the target, the electron also affects the density of the ions. The findings indicate that the presence of a stationary magnetic field in close proximity to a plasma significantly regulated the migratory rate of cancer cells.Figure 1. (Ⅰ) scratch healing assay, (Ⅱ) percentage of gap for treatments, (Ⅲ) electron temperature calculation with Boltzmann plot.[1] S. Padureanu et al., “Non-Thermal Plasma-Activated Water: A Cytogenotoxic Potential on Triticum aestivum,” Agronomy, vol. 13, no. 2, 2023, doi: 10.3390/agronomy13020459.[2] V. Ioannou and S. Laizet, “Numerical investigation of plasma-controlled turbulent jets for mixing enhancement,” Int. J. Heat Fluid Flow, vol. 70, no. October 2017, pp. 193–205, 2018, doi: 10.1016/j.ijheatfluidflow.2018.02.008.[3] L. Guo et al., “Mechanism of virus inactivation by cold atmospheric-pressure plasma and plasmaactivated water,” Appl. Environ. Microbiol., vol. 84, no. 17, 2018, doi: 10.1128/AEM.00726-18.[4] X. Cheng et al., “Enhancing cold atmospheric plasma treatment of cancer cells by static magnetic field,” Bioelectromagnetics, vol. 38, no. 1, pp. 53–62, 2017, doi: 10.1002/bem.22014.[5] R. Mehrabifard, H. Mehdian, K. Hajisharifi, and E. Amini, “Improving Cold Atmospheric Pressure Plasma Efficacy on Breast Cancer Cells Control-Ability and Mortality Using Vitamin C and Static Magnetic Field,” Plasma Chem. Plasma Process., vol. 40, no. 2, pp. 511–526, Nov. 2020, doi: 10.1007/s11090-019-10050-5.[6] R. Mehrabifard, Z. Kabarkouhi, F. Rezaei, K. Hajisharifi, H. Mehdian, and E. Robert, “Physical understanding of the static magnetic field’s synergistic enhancement of cold atmospheric pressure plasma treatment,” Apr. 2023, Accessed: Sep. 21, 2023. [Online]. Available: https://arxiv.org/abs/2304.05833v1 Figure 1