In order to explore the bioelectric effect of 5 ns pulsed electric fields on tumor cells, a spherical single-cell multiphysics model was first established based on the finite element simulation platform. In consideration of the dielectric relaxation of the biological plasma membrane under the high-frequency electric fields, the electroporation and Maxwell stress tensors on the cell membrane and nuclear envelope were analyzed; secondly, taking MDA-MB-231 cells as the research object, combined with fluorescent probe technology, the state change and fluorescence dissipation of its subcellular structure exposed to pulse fields were studied. The results showed that 5 ns pulsed electric fields directly acted inside the cell, causing an electroporation effect and tensile stress on the nuclear envelope, destroying the integrity and order of the cytoskeleton, and damaging the functions of subcellular structures including endoplasmic reticulum, mitochondria, etc. This study provides theoretical and experimental evidence for the research and application of a high-voltage short pulse in the field of biomedical engineering.

The biological response to short pulses with a width on the order of ten nanoseconds is still blur for lacking of a dependable high-voltage ultrashort pulse power module (HVUPPM). Therefore, this article introduces a HVUPPM with high output/input voltage gain and high repetition rates. First, the proposed HVUPPM utilizes a short-circuit secondary side transformer (SSST) as an intermediate energy storage component and generates high-voltage nanosecond pulses based on inductive energy storage. Analyzed the impact of parasitic parameters on waveforms and verified the analysis results through simulation. Secondly, in order to further improve the output voltage, a twisted pair transformer (TPT) with low leakage inductance is used as the power superposition element of HVUPPM to increase the output voltage amplitude and suppress waveform distortion. Finally, a prototype was developed to verify the functionality of the proposed HVUPPM and TPT. The prototype can output pulses with a half-peak width of 13 ns and an amplitude of 5.2 kV, achieving an output/input voltage gain of 400. In burst mode, it can generate unipolar pulses with a repetition frequency of up to 2 MHz and bipolar pulses with repetition rates in the MHz range.