Monitoring the molecular composition of live cells exposed to electric pulses via label-free optical methods.

The permeabilization of the live cells membrane by the delivery of electric pulses has fundamental interest in medicine, in particular in tumors treatment by electrochemotherapy. Since underlying mechanisms are still not fully understood, we studied the impact of electric pulses on the biochemical composition of live cells thanks to label-free optical methods: confocal Raman microspectroscopy and terahertz microscopy. A dose effect was observed after cells exposure to different field intensities and a major impact on cell peptide/protein content was found.

A wide-band bio-chip for real-time optical detection of bioelectromagnetic interactions with cells.

The analytical and numerical design, implementation, and experimental validation of a new grounded closed coplanar waveguide for wide-band electromagnetic exposures of cells and their optical detection in real-time is reported. The realized device fulfills high-quality requirements for novel bioelectromagnetic experiments, involving elevated temporal and spatial resolutions. Excellent performances in terms of matching bandwidth (less than -10 dB up to at least 3 GHz), emission (below 1 × 10 W/m) and efficiency (around 1) have been obtained as revealed by both numerical simulations and experimental measurements.

Cell Membrane Electropulsation: Chemical Analysis of Cell Membrane Modifications and Associated Transport Mechanisms.

The transport of substances across the cell membrane is complex because the main physiological role of the membrane is the control of the substances that would enter or exit the cells. Life would not be possible without this control. Cell electropulsation corresponds to the delivery of electric pulses to the cells and comprises cell electroporation and cell electropermeabilization.

Comprehensive Characterization of the Interaction between Pulsed Electric Fields and Live Cells by Confocal Raman Microspectroscopy.

This study reports a comprehensive analysis of the effect of 100 μs electric pulses on the biochemical composition of live cells using a label-free approach, confocal Raman microspectroscopy. We investigated different regions of interest around the nucleus of the cells and the dose-effect relationship related to different electric pulse parameters. We also extended the study to another cell type.

Demonstration of the Protein Involvement in Cell Electropermeabilization using Confocal Raman Microspectroscopy.

Confocal Raman microspectroscopy was used to study the interaction between pulsed electric fields and live cells from a molecular point of view in a non-invasive and label-free manner. Raman signatures of live human adipose-derived mesenchymal stem cells exposed or not to pulsed electric fields (8 pulses, 1 000 V/cm, 100 μs, 1 Hz) were acquired at two cellular locations (nucleus and cytoplasm) and two spectral bands (600-1 800 cm and 2 800-3 100 cm). Vibrational modes of proteins (phenylalanine and amide I) and lipids were found to be modified by the electropermeabilization process with a statistically significant difference.

A Novel Spectroscopically Determined Pharmacodynamic Biomarker for Skin Toxicity in Cancer Patients Treated with Targeted Agents.

Raman spectroscopy is a noninvasive and label-free optical technique that provides detailed information about the molecular composition of a sample. In this study, we evaluated the potential of Raman spectroscopy to predict skin toxicity due to tyrosine kinase inhibitors treatment. We acquired Raman spectra of skin of patients undergoing treatment with MEK, EGFR, or BRAF inhibitors, which are known to induce severe skin toxicity; for this pilot study, three patients were included for each inhibitor.

Interpulse multifrequency electrical impedance measurements during electroporation of adherent differentiated myotubes.

In this study, electrical impedance spectroscopy measurements are performed during electroporation of monolayers of differentiated myotubes. The time resolution of the system (1 spectrum/ms) enable 860 full spectra (21 frequencies from 5 kHz to 1.3 MHz) to be acquired during the time gap between consecutive pulses (interpulse) of a classical electroporation treatment (8 pulses, 100 μs, 1 Hz).