Dielectric spectroscopy of biological cells in microfluidic devices
Résumé
This work is focused in the area of ligandreceptor interaction analysis, working with a wellcharacterized biological model (ligand: lactoferrin, receptors: nucleolin and sulfated proteoglycans). The purpose is to be able to assign, in real time, a specific crossing pathway to a ligand/receptor pair, without the use of molecular labels. The classification is based on changes in the electrical properties of the cells. We propose to follow the various phases of assembly between the ligand and receptors present or not on a set of mutant CHO cell lines, and internalization of the ligands/receptors complexes into the cells. Various BioMEMS have been designed and fabricated in order to characterize the variation of the electrical properties of the biological cells. We are interested in both dielectric (i.e. polarization) and vibrationnal (i.e. absorption) spectroscopy. Several devices are currently tested for low (<10MHz) and high (>40GHz) frequency range (LFR & HFR) measurements. In the LFR, we have fabricated coplanar and 3D electrodes sensors for impedance measurements. In the HFR, we have designed and processed coplanar waveguides.