ELECTRICAL CHARACTERIZATION OF CANCER CELLS

Abstract

In this work, the impedance of different cancer cell lines was measured using a lab-on-chip device developed by imec (interuniversity electronics center) in Leuven, Belgium. The motivation of this thesis is the detection of circulating tumour cells (CTCs) from cancer metastatic patients. Currently CTC detection is challenging because of the low abundance and phenotype similarity with white blood cells. Imec is developing a proprietary transistor-embedded device for massively parallel on-chip single cell characterization in the European project MIRACLE (Magnetic Isolation and moleculaR Analysis of single CircuLating and disseminated tumor cElls on chip). This chip is composed of thousands of measurement units for electrical impedance spectroscopy. The first step of this work was measuring the impedance of different ionic strength solutions, in order to validate the equivalent circuit theoretical model, previously developed using the software Matlab and some literature data. The second step was measuring the impedance of different cancer cell lines. A positive correlation between the cell membrane capacitance and the cell malignancy was seen. This was attributed to some changes, which happen during the cancerization process, such as cellular membrane and tight junctions destruction, which lead to an increased permeability and membrane potential reduction. These results agrees with some literature. The last step was measuring the electrical impedance of cell membrane after incubation with a drug, named Paclitaxel, which acts specifically on cell microtubes, connected to the cell membrane. Treating the cells with drug is responsible of a variation of cell membrane impedance, which may be use as a criterion to differentiate different cancer cell lines. However, further work is necessary.