The construction of an individually addressable cell array for selective patterning and electroporation

Abstract

In basic cell biology research and drug discovery, it is important to rapidly introduce genes, proteins or drug compounds into cells without permanent damage. Here, we report a three dimensional SU-8 micro-well structure sandwiched with an indium tin oxide (ITO) electrode-covered slide from the top and an individually addressable array of microelectrodes on the bottom to allow parallel delivery of exogenous molecules into various cells in a spatially specific manner. A positive dielectrophoretic force was selectively applied by energizing appropriate electrodes to capture the dispersed cells at the bottom electrode, while the micro-wells were designed to confine cells in situ when the positive dielectrophoretic force is removed. The combination of spatial positive dielectrophoresis (pDEP) and micro-wells made it possible to construct cell microarrays with specific patterns. Once the cells become attached to the electrodes, different plasmids can be introduced sequentially for selective electroporation. The present cell arraying-assisted electroporation chip integrates a pDEP-assisted cell positioning function with selective electroporation to provide a simple and efficient method for gene transfer. This platform is ideal for high throughput screening of compounds in parallel and thus holds promise for applications in cellular and molecular research.

Micro- and Nanoscale Technologies for Delivery into Adherent Cells

“…Microwell-based microfluidic electroporation devices (see Microwell-E in Figure 2) typically consist of an array of microwells, with diameters in the range of 100–500 µm, assembled with microelectrodes (patterned metallic films on Si or glass substrates) [26, 27]. Input voltages of <30 V are typically used due to the small distance between electrodes, which is often referred to as microelectroporation.…”

“…Owing to the array structure, these devices are often designed to be compatible with conventional microarray readers for high throughput analysis. Recently, a cell arraying-assisted electroporation (CAE) chip [26] was developed where cells can be effectively positioned into each microwell using dielectrophoretic and hydraulic forces. For selective electroporation, an array of microwells were registered with an array of independent microelectrodes such that a small population of cells in a particular microwell can be selectively electroporated.…”

“…Electroporation has been used in both lab-on-a-chip (left column) and nanoprobe (right column) configurations including (counterclockwise) localized electroporation device (LEPD), and microwell-, nanopipette-, and nanofountain-electroporation (Microwell-E, Nanopipette-E, and NFP-E), respectively. These figures are reproduced from [3] and [26], [78], and [18] with permission of The Royal Society of Chemistry, The Japan Society of Applied Physics, and American Chemical Society, respectively.…”

Precise transportation of single cell by phase-shift standing surface acoustic wave

“…Continuous transportation of single cell in a fluid medium is of crucial interest not only for basic cell biology but also for clinical medicine, cancer research and gene therapy [1][2][3]. There are various methods to transport the cells, such as electrophoresis [4,5], magnetic tweezers [6,7] and acoustic field [8,9].…”

Microfluidic Bioreactors for Cell Culturing: A Review

“…Since its inception in 1982, by Neumann et al, [160] electroporation has been widely used due to its ability to achieve rapid high electrical lysis with disruptions times as low as 33ms, about eight times as faster than SDS [161]. Recently Xu et al [162], developed a cell arraying-assisted electroporation (CAE) chip which uses both the positive dielectrophoresis and electroporation techniques to provide a simple and efficient method for gene transfer. The CAE chip in microelectrode array format is covered with SU-8 microwell structures to facilitate both cell positioning and electroporation.…”