Electrical Monitoring during Non-Thermal Plasma Treatment of Cell Suspensions

The current understanding of the effects of nonthermal plasma (NTP) on living cells extends beyond plasma induced chemistry to include physical effects such as electric and electromagnetic fields. In addition, there is a growing recognition of the feedback effects of the treated cell suspensions on the properties of the applied NTP. The concept of adaptive plasma that changes as it both alters the substrate and adjusts in response to the properties of the treated material, has been suggested as a way to control plasma applications. In this study we explore the changes in the properties of the applied NTP depending on the type and the viability of cells during an in vitro treatment of cell suspensions. Cell suspensions are treated with NTP produced by a floating electrode dielectric barrier discharge and therefore become a part of the overall electrical circuit. Operando electrical measurements are used to determine the load impedance and changes thereof for various cell suspensions. We compare the changes in the impedance of cell media, live Viro cells, and cells of reduced viability, since these changes affect the properties of the NTP during treatment. This study confirms that the control of the power input conditions and treatment time are insufficient for the control of NTP dose in biomedical applications.