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Open access

Vitalij Novickij, Audrius Grainys, Jurij Novickij, Sonata Tolvaisiene and Svetlana Markovskaja

Abstract

Subjection of biological cells to high intensity pulsed electric field results in the permeabilization of the cell membrane. Measurement of the electrical conductivity change allows an analysis of the dynamics of the process, determination of the permeabilization thresholds, and ion efflux influence. In this work a compact electro-permeabilization system for controlled treatment of biological cells is presented. The system is capable of delivering 5 μs - 5 ms repetitive square wave electric field pulses with amplitude up to 1 kV. Evaluation of the cell medium conductivity change is implemented in the setup, allowing indirect measurement of the ion concentration changes occurring due to the cell membrane permeabilization. The simulation model using SPICE and the experimental data of the proposed system are presented in this work. Experimental data with biological cells is also overviewed

Open access

Audrius Grainys, Jurij Novickij, Tomaš Stankevič, Voitech Stankevič, Vitalij Novickij and Nerija Žurauskienė

Abstract

In this work we present a mobile 43 kJ pulsed magnetic field facility for single pulse calibration of magnetic field sensors. The magnetic field generator is capable of generating magnetic fields up to 40 T with pulse durations in the range of 0.3-2 ms. The high power crowbar circuit is used for the reverse voltage protection and pulse shaping purposes. The structure, the development challenges and the implemented solutions to improve the facility for the calibration of the magnetic field sensors are overviewed. The experimental data of the application of the proposed generator for the calibration of manganite magnetic field sensors are presented.

Open access

Vitalij Novickij, Irutė Girkontaitė, Audrius Grainys, Auksė Zinkevičienė, Eglė Lastauskienė, Jurgita Švedienė, Algimantas Paškevičius, Svetlana Markovskaja and Jurij Novickij

Abstract

Electroporation is an electric field induced phenomenon occurring when the permeability of the cell membrane is increased due to the excess of critical transmembrane potential. Fluorescent dye assays are frequently used for evaluation of the permeabilization rate, however, the protocols vary, which negatively affects the repeatability of the results. In this work we have designed experiments to investigate the protocols and threshold concentrations of the Propidium Iodide (PI) and YO-PRO-1 (YP) fluorescent dyes for evaluation of mammalian cell permeabilization induced by electroporation. The Sp2/0 mouse myeloma cells were used and the bursts of 100 μs × 8 electrical pulses of 0.8-2 kV/cm were applied. It has been shown that the dye concentration has an influence on the detectable permeabilization, and the concentrations below 30 μM for PI and 1 μM for YP should be avoided for measurement of electropermeabilization efficacy due to unreliable fluorescence signals. Further, based on the experimental data, the permeabilization curve for the Sp2/0 myeloma cells in the 0.8-2 kV/cm range has been presented.