Insulator‐based dielectrophoretic single particle and single cancer cell trapping

Abstract

Trapping of individual cells at specific locations in a microfluidic lab-on-a-chip platform is essential for single cell studies, especially those requiring individual stimulation followed by downstream analysis. To this aim, we have designed microdevices based on direct current (DC) insulator-based dielectrophoresis (iDEP) acting as individual single cell traps. We present both the design of a negative iDEP trap and a positive iDEP trap using insulating posts integrated at microchannel intersections. We obtained electric field distributions via numerical simulations adapted to the intersection and trap geometry with which we predict single particle pathlines. With polystyrene particles of 10 μm diameter, we demonstrated an effective design for a single particle trap in the case of negative dielectrophoresis. The onset trapping voltage shows an inverse relation to the buffer conductivity, thus indicating the influence of electrokinetic effects on the trapping behavior. Additionally, we demonstrated the proof-of-principle of single MCF-7 breast cancer cell trapping in a positive iDEP trap. Our single particle trapping experiments were further in very good agreement with numerical simulations. To ensure that no significant damage occurred to the cells during the experiment, we further optimized medium conditions to ensure viability of the cells for at least 1 h, more than sufficient for microfluidic trapping experiments. Our results thus indicated the successful design of DC iDEP traps, which can easily be integrated into a variety of microchip operations for single cell analysis.

Characterization of a hybrid dielectrophoresis and immunocapture microfluidic system for cancer cell capture

“…A majority of DEP cancer cell isolation techniques use model cancer cell lines spiked in buffer media or diluted blood; such techniques include DEP flowfield fractionation (DEP-FFF) [33][34][35][36], insulative and contactless DEP [37][38][39][40], and streamline separations using angled electrodes [41][42][43][44]. These studies separate cancer cells from other blood constituents based on their differences in DEP response in a specific applied frequency range.…”

Isolation and enrichment of low abundant particles with insulator-based dielectrophoresis

“…24,[35][36][37] For further information on the mathematical modeling of iDEP systems, we refer the reader to studies available in the literature. 24,35,38 …”

Dielectrophoretic concentrator enhancement based on dielectric poles for continuously flowing samples

“…When a homogeneous isotropic particle that is polarized linearly is considered, the dielectrophoretic force is defined by (1) [30][31]:…”

“…All these structures are especially powerful and suitable to be used to trap or concentrate such small cells and even single cells, as it has been demonstrated. As S.Bhattacharya et al reported [30]it is possible to trap a single 10 µm MCF.7 breast cancer cell by means of positive DEP. Also, H.H.…”