Impact of external medium conductivity on cell membrane electropermeabilization by microsecond and nanosecond electric pulses

Abstract

The impact of external medium conductivity on the efficiency of the reversible permeabilisation caused by pulsed electric fields was investigated. Pulses of 12 ns, 102 ns or 100 μs were investigated. Whenever permeabilisation could be detected after the delivery of one single pulse, media of lower conductivity induced more efficient reversible permeabilisation and thus independently of the medium composition. Effect of medium conductivity can however be hidden by some saturation effects, for example when pulses are cumulated (use of trains of 8 pulses) or when the detection method is not sensitive enough. This explains the contradicting results that can be found in the literature. The new data are complementary to those of one of our previous study in which an opposite effect of the conductivity was highlighted. It stresses that the conductivity of the medium influences the reversible permeabilization by several ways. Moreover, these results clearly indicate that electropermeabilisation does not linearly depend on the energy delivered to the cells.

Technological and Theoretical Aspects for Testing Electroporation on Liposomes

“…The researchers agree that, in biological issues resolution, the cooperation between experiments and modeling must be considered as a fundamental step [12, 16, 27, 28]. In particular, this aspect is critical and significant when one wants to investigate the interactions between the electromagnetic fields and the biological objects.…”

“…Moreover, with the advances in micro- and nanofabrication techniques, some microdevices are proposed for nanosecond exposure, integrated also with a microfluidic system [16, 19, 22, 23]. A typical applicator is a standard electroporation cuvette consisting of two plate parallel electrodes with a gap of 4, 2, or 1 mm [12, 13, 18, 20]. In particular, the 1 mm gap cuvette permits generating higher values of the electric field in the solution, but in such cases the matching with the 50 Ω of the pulse generator can be critical [17, 20].…”

Effects of extracellular medium conductivity on cell response in the context of sub-microsecond range calcium electroporation

“…In this work, we present experimental data on extracellular medium conductivity effects during electroporation in the submicrosecond range (100 ns-900 ns) using mouse colon carcinoma MC38/0 cell line as a model. We superposition our data with available studies 10,11 in the nanosecond range using 25 ns pulses of 60 kV/cm. To maximize the consolidation of knowledge and to provide a reference for the described efficacies, we also cover the conventional microsecond range (100 μs × 8) pulses.…”

On the possible mechanisms of the selective effect of a non‐equilibrium plasma on healthy and cancer cells in a physiological solution

“…Currents can be excited without plasma when electrodes are immersed in the electrolyte, to which a potential difference is applied ( Fig. 1(B)) [11][12][13][14][15]. These ion currents can lead to an additional charge of cell membranes, thus changing the transmembrane potential difference.…”

“…In [11][12][13], it was experimentally shown that the critical field strength for the lysing of bacteria (prokaryotic cells) is around 0.1-1 V across the cell membrane, depending on exposure time. In [15], experimental results were given for the influence of electric fields of varying intensity and duration on cancer cells at different values for the medium's conductivity [15]. It was shown that, as the medium's salinity (conductivity) increases, the electric field at which cell death occurs begins to fall.…”