Dielectrophoretic manipulation of cancer cells and their electrical characterization.

Electromanipulation and electrical characterization of cancerous cells is becoming a topic of higher interest as the results reported to date demonstrate a good differentiation among various types of cells from electrical viewpoint. Dielectrophoresis (DEP) and broadband dielectric spectroscopy (BDS) are complimentary tools for sorting, identification and characterization of malignant cells and were successfully used on both primary tumor cells and culture cells as well. However, the literature is presenting a plethora of studies in respect to electrical evaluation of this type of cells and this paper is reporting a collection of information regarding the functioning principles of different types of dielectrophoresis set-ups, theory of cancer cells polarization and electrical investigation (including here the polarization mechanisms). The interpretation of electrical characteristic against frequency is discussed in respect to interfacial/Maxwell Wagner polarization and the parasitic influence of electrode polarization. Moreover, the electrical equivalent circuits specific to biological cells polarizations are discussed for a good understanding of cells' morphology influence. The paper also focuses on advantages of specific low-conductivity buffers employed currently for improving the efficiency of dielectrophoresis and provides a set of synthesized data from literature highlighting clear differentiation between the crossover frequencies of different cancerous cells.