Experimental Microdosimetry Techniques for Biological Cells Exposed to Nanosecond Pulsed Electric Fields Using Microfluorimetry

Abstract

International audienceIn the last decade, high-intensity pulsed electric fields with nanosecond durations (3-300 ns) have found breakthrough biomedical applications, e.g., in cancer treatment and gene therapy; however, the physical mechanisms underlying the interaction between nanosecond pulsed electric fields (nsPEFs) and cells, tissues, or organs are not yet fully elucidated. The precise knowledge of the electromagnetic dose received by the exposed sample at the macroscopic, and better still at the microscopic scale, is essential to complete our understanding of the phenomena involved and for adequate interpretation and reproducibility of the results. In this paper, we report a dosimetric and microdosimetric study of an in vitro exposure setup based on a transverse electromagnetic (TEM) cell that allows the exposure of cells in a Petri dish to nsPEFs. The rectangular and bipolar pulses delivered to the cells had a total duration of 1.2 ns and an amplitude of 2 kV. The electric field in situ was characterized experimentally with a nonmetallic probe and numerically using a finite-difference time-domain algorithm. Results of real-time monitoring of temperature were obtained at the subcellular level by using microfluorimetry, which is a method of imaging temperature by using a fluorescent molecular probe with thermosensitive properties

Calcium-independent disruption of microtubule dynamics by nanosecond pulsed electric fields in U87 human glioblastoma cells

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Rhodamine B as an optical thermometer in cells focally exposed to infrared laser light or nanosecond pulsed electric fields

“…These properties lead us to test whether RhB dye could be successfully used as optical thermometer in small biological compartments at the subcellular level. It has been used recently in the measurement of temperature in rat tail tendon samples exposed to radiofrequency electromagnetic fields [31], and similarly used in our group to measure temperature in cells exposed to continuous wave microwaves [32].…”

Electromagnetic Analysis of an Aperture Modified Tem Cell Including an Ito Layer for Real-Time Observation of Biological Cells Exposed to Microwaves

“…It is known that small TEM cells have a high useful frequency band. We have previously used the TEM cell shown in Figure 1 as a delivery system for microwaves [8,9,14,27,28] and for nanosecond electric pulses [17,29,30]. The biological sample was placed in a 35-mm Petri dish centered above the TEM cell lower plate.…”

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