In this paper, delivery devices for nanosecond pulsed electric field exposure of biological samples in direct contact with electrodes or isolated are presented and characterized. They are based on a modified electroporation cuvette and two transverse electromagnetic cells (TEM cells). The devices were used to apply pulses with high intensity (4.5 kV) and short durations (3 and 13 ns). The delivery devices were electromagnetically characterized in the frequency and time domains. Field intensities of around 5, 0.5, and 12 MV m were obtained by numerical simulations of the biological sample positioned in the three delivery devices. Two delivery systems had a homogenous electric field spatial distribution, and one was adapted to permit a highly localized exposure in the vicinity of a needle. Experimental biological investigations were carried out at different field intensities for five cancer cell lines. The results using flow cytometry showed that cells kept polarized mitochondrial membrane but lost plasma membrane integrity following a dose-response trend after exposure to different electric field intensities. Certain cell types (U87, MCF7) showed higher sensitivities to nsPEFs than other lines tested.

In this study, an electrical device is proposed to generate plasmas in nanosecond dielectric barrier discharge (nsDBD) configuration and to measure the electrical parameters of the discharge over a large bandwidth. Electrical parameters were experimentally determined using a common dielectric barrier discharge equivalent circuit extended here to high frequencies. An efficient synchronization procedure based on a comparison to circuit simulation results was proposed. Discharge current pulses with rise times less than 1 ns and amplitudes up to 50 A were measured. The energy deposited into the plasma and the discharge resistance were determined as a function of time. In addition, circuit simulations support the experimental approach. The nsDBD was accurately modeled by a resistance of the plasma channel following a Rompe and Weizel law in series with a resistance for the discharge spreading along the dielectric surface and a sheath capacitance.