Microfluidics cell electroporation

Abstract

Electroporation or electropermeabilization is one of the most powerful biological techniques in cell studies. Applying the high voltage electric field in vicinity of the cells can generate nanopores in cell membrane. Varying with the intensity and the duration of these applied electric field, the created nanopores can be temporary (reversible electroporation) or permanent (irreversible electroporation). Reversible electroporation is usually conducted to insert biological samples into the cells. Cells are also electroporated irreversibly to release their intercellular contents for further biological investigations. In comparison with the conventional electroporation devices, microfluidic (microscale) electroporation devices have some advantages such as higher cell viability rate, high transfection efficiency, lower sample contamination, and smaller Joule heating effect. In this article, the latest advancement in microfluidic cell electroporation is reviewed. First, the underlying theory of membrane permeabilization is reviewed and the leading analytical studies on the cell electroporation are presented. Following that, different experimental methods are compared. Finally, some suggestions are proposed for the future studies.

In vitro and ex vivo strategies for intracellular delivery

“…4a). They can reduce the required voltage (often by 100-fold), provide superior heat dissipation, and incorporate flexible design features, such as hydrodynamic focusing to distance cells from potentially damaging electrodes 78 . An elegant and electroporation system that uses a ~90-nanometre aperture to localize the permeabilization to a single point on the cell surface.…”

Continuous medium exchange and optically induced electroporation of cells in an integrated microfluidic system

“…In the past few decades, single-function microfluidic components capable of performing specific tasks, such as cell separation [1][2][3][4] , particle/cell focusing 5 and cell electroporation [6][7][8] , have been thoroughly investigated as stand-alone components in a variety of microfluidic applications. However, in terms of replacing a traditional clinical laboratory with a single lab-on-a-chip, most of these stand-alone microfluidic components were not sufficient to address practical problems that require multiple processing steps.…”

“…In comparison to conventional electroporation methods, microfluidic systems have some advantages, including the use of a lower applied electric field, lower sample and reagent consumption and reduced Joule heating 6 . However, existing microfluidic electroporation devices with fixed micro-electrodes are incapable of exchanging media in a sample pre-treatment step.…”

Recent Trends on Micro/Nanofluidic Single Cell Electroporation

“…where φ i − φ e is the potential difference between intracellular and extracellular membrane, r is the radius of the cell, E 0 is the applied electric field strength and θ is the angle between direction of electric field and the selected point of the cell surface [13,14]. To apply high external electric field with longer pulses (ms), TMP can increase and hydrophobic pores became hydrophilic one at threshold TMP values (0.2-1 V) [6,[15][16][17][18][19].…”

“…As a result, single cell manipulation can be performed from population of cells together. These devices can analyze cell to cell behavior with their organelle, their orientation, changes of cell size and shape with different polarities of electric fields [14,23,24,26,27]. On the other hand, bulk electroporation needs two large electrodes surrounding millions of cells together and a homogeneous electric field is applied to electroporates millions of cells at once.…”