Enrichment of diluted cell populations from large sample volumes using 3D carbon-electrode dielectrophoresis

Abstract

Here, we report on an enrichment protocol using carbon electrode dielectrophoresis to isolate and purify a targeted cell population from sample volumes up to 4 ml. We aim at trapping, washing, and recovering an enriched cell fraction that will facilitate downstream analysis. We used an increasingly diluted sample of yeast, 10 6 -10 2 cells/ml, to demonstrate the isolation and enrichment of few cells at increasing flow rates. A maximum average enrichment of 154.2 6 23.7 times was achieved when the sample flow rate was 10 ll/min and yeast cells were suspended in low electrically conductive media that maximizes dielectrophoresis trapping. A COMSOL Multiphysics model allowed for the comparison between experimental and simulation results. Discussion is conducted on the discrepancies between such results and how the model can be further improved. Published by AIP Publishing.

Dielectrophoretic Separation of Live and Dead Monocytes Using 3D Carbon-Electrodes

“…Fabrication of 3D glass-like carbon-microelectrodes has been explained in detail [ 40 , 41 , 42 , 43 , 66 ]. In brief, two-step photolithography process of SU-8 (Gersteltec, Pully, Switzerland), a negative-tone photoresist, on a silicon wafer was applied to create the 3D structure of the microelectrodes.…”

“…Finally, carbon-electrodes have excellent biocompatibility and mechanical properties, as reported in [ 39 ]. Since the height of the electrodes is taller in 3D carbon-DEP chips, the inner volume of the DEP chip can be used more efficiently to generate high-throughput [ 40 , 41 ]. The advantages of 3D carbon-DEP chips have been reported using various sample types such as particles [ 40 ], yeast cells [ 41 ], bacteria [ 42 ] and DNA [ 43 ].…”

Dielectrophoretic characterization and separation of monocytes and macrophages using 3D carbon‐electrodes

“…The fabrication stages of 3D glass‐like carbon‐microelectrodes have been described in our previous studies . Basically, the 3D structure of the electrodes was created with two‐step photolithography process of SU‐8 (Gersteltec, Pully, Switzerland) on a silicon wafer.…”

“…Utility of the carbon‐electrodes advance the usability and throughput of DEP separation while exhibiting wider electrochemical stability. Its electromechanical properties enable generating suitable electric field without electrolysis of the cells .…”

Assessing the importance of the root mean square (RMS) value of different waveforms to determine the strength of a dielectrophoresis trapping force

“…A microchannel made with double‐sided pressure‐sensitive adhesive contained the electrode array. The reader is referred to our previous publications to consult the fabrication details of these flow‐through carbon‐electrode DEP devices . Particles were suspended in distilled water at a concentration of 10 7 /mL.…”