Electrical characteristics analysis of various cancer cells using a microfluidic device based on single-cell impedance measurement

Electrical impedance spectroscopy (EIS) is used to analyze the characteristics of electrochemical materials for biomedical applications. This paper presents a method for differentiating four kinds of cell using impedance measurements at various voltages and frequencies. Four kinds of cell (HeLa, A549, MCF-7, and MDA-MB-231) are analyzed and characterized based on their impedance by a trap-and-measure device. The impedance spectra are obtained by the impedance analyzer at an operating voltage of 0.2-1.0 V and frequency of 20-101 kHz. According to the impedance measurements, HeLa. A549, and MCF-7 cells and the pathological stages of a given cancer cell line (MCF-7 and MDA-MB-231) can be distinguished. The equivalent circuit is modeled as a cell impedance in parallel with the impedance of the culture medium, a cell impedance that contains the cell membrane capacitance, and a cytoplasm resistance. With an increase in the operating voltage, the cytoplasm resistance decreases due to the opening of the ionic channel. For A549, MDA-MB-231, MCF-7, and HeLa cells, the maximum variation of the resistance was obtained in the voltage ranges of 0.8-1.0 V. 0.8-1.0 V. 0.6-0.8 V. and 0.4-0.6 V. respectively. The results reveal that different kinds of cell have different tolerances to an electric field. (C) 2012 Elsevier B.V. All rights reserved.