High Frequency Bipolar Electroporator with Double-Crowbar Circuit for Load-Independent Forming of Nanosecond Pulses

Abstract

In this work, a novel electroporation system (electroporator) is presented, which is capable of forming high frequency pulses in a broad range of parameters (65 ns–100 µs). The electroporator supports voltages up to 3 kV and currents up to 40 A and is based on H-bridge circuit topology. A synchronized double crowbar driving sequence is introduced to generate short nanosecond range pulses independently of the electroporator load. The resultant circuit generates pulses with repetition frequencies up to 5 MHz and supports unipolar, bipolar, and asymmetrical pulse sequences with arbitrary waveforms. The shortest pulse duration step is hardware limited to 33 ns. The electroporator was experimentally tested on the H69AR human lung cancer cell line using 20 kV/cm bipolar and unipolar 100 ns–1 μs pulses. Based on a YO-PRO-1 permeabilization assay, it was determined that the electroporator is suitable for applied research on electroporation. The system offers high flexibility in experimental design to trigger various electroporation-based phenomena.

Does the shape of the electric pulse matter in electroporation?

“…A typical solution is to shunt the load with low parallel resistance ( 25 ) or introduce active circuitry to form the pulse independently on the load ( 26 ). In the first case, such a solution will influence higher voltage droop, and in the second case, the complexity of the circuit and its driving increase dramatically.…”

“…Novickij et al. developed a device for 65 ns–100 µs asymmetric pulse generation in 2022 ( 26 ). It could be speculated that the high-energy asymmetric nanosecond pulses will elicit stronger and more selective effects on intracellular membranes than symmetrical pulses.…”