Investigating the characteristics of 11 kHz excitation of EFCAP and its selective effect on breast cancer cell death

Recently developed excitation frequency-controlled cold atmospheric pressure plasma has shown its efficacy in producing tunable effects with different excitation frequencies in terms of reactive species generation and cancer cell death. This study investigates the electron number density of plasma produced at 11 kHz excitation from stark broadened H & alpha; line, discharge characteristics through simultaneous recording of voltage-current signals, and high-speed images of the discharge zone. Malignant breast cancer cells (MCF-7) and nonmalignant breast cells (MCF-10A) were used in selectivity experiments. Proliferation and clonogenic assays revealed selective death of cancer cells. DNA damage and DNA repair kinetics were studied using time-dependent & gamma;-H2AX foci formation assessment and the selective killing of cancerous cells was established for the 60 s of plasma treatment.