Microfluidic devices for manipulation, modification and characterization of biological cells in electric fields – a review

This article presents use of electric field for manipulation of biological cells and modification of their physical properties in microfluidic chambers. Some fabrication procedures of electrodes and microfluidic chambers are presented, from thin film metal electrodes to three-dimensional structures. Strong electric field pulses induce formation of pores in cell membrane (electroporation), which allow for transport of physiologically membrane-impermeant molecules into the cell. Even stronger electric fields cause nonthermal cell lysis, which is useful in the extraction and analysis of intracellular components. Dielectrophoresis in an inhomogeneous electric field is used for manipulation of cells (e.g. guiding and patterning), characterization of their electrical properties, detection of rare cells, as well as for separation of different cells. Electroporation and dielectrophoresis can be used together on a single chip, where dielectrophoresis is used for positioning of cells where they are electroporated, which is often used for electrofusion of cells.