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Abstract Circulating tumor cells (CTCs) have been proven to have significant prognostic, diagnostic, and clinical values in early‐stage cancer detection and treatment. The efficient separation of CTCs from peripheral blood can ensure intact and viable CTCs and can, thus, give proper genetic characterization and drug innovation. In this study, continuous and high‐throughput separation of MDA‐231 CTCs from overlapping sized white blood cells (WBCs) is achieved by modifying inertial cell focusing with dielectrophoresis (DEP) in a single‐stage microfluidic platform by numeric simulation. The DEP is enabled by embedding interdigitated electrodes with alternating field control on a serpentine microchannel to avoid creating two‐stage separation. Rather than using the electrokinetic migration of cells which slows down the throughput, the system leverages the inertial microfluidic flow to achieve high‐speed continuous separation. The cell migration and cell positioning characteristics are quantified through coupled physics analyses to evaluate the effects of the applied voltages and Reynolds numbers (Re) on the separation performance. The results indicate that the introduction of DEP successfully migrates WBCs away from CTCs and that separation of MDA‐231 CTCs from similar sized WBCs at a highReof 100 can be achieved with a low voltage of magnitude 4 ×106 V/m. Additionally, the viability of MDA‐231 CTCs is expected to be sustained after separation due to the short‐term DEP exposure. The developed technique could be exploited to design active microchips for high‐throughput separation of mixed cell beads despite their significant size overlap, using DEP‐modified inertial focusing controlled simply by adjusting the applied external field.
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Three‐dimensional lab‐on‐a‐foil device for dielectrophoretic separation of cancer cells
Abstract A simple, low‐cost, three‐dimensional (3D) lab‐on‐a‐foil microfluidic device for dielectrophoretic separation of circulating tumor cells (CTCs) is designed and constructed. Disposable thin films are cut by xurography and microelectrode array are made with rapid inkjet printing. The multilayer device design allows the studying of spatial movements of CTCs and red blood cells (RBCs) under dielectrophoresis (DEP). A numerical simulation was performed to find the optimum driving frequency of RBCs and the crossover frequency for CTCs. At the optimum frequency, RBCs were lifted 120 µm inz‐axis direction by DEP force, and CTCs were not affected due to negligible DEP force. By utilizing the displacement difference, the separation of CTCs (modeled with A549 lung carcinoma cells) from RBCs inz‐axis direction was achieved. With the nonuniform electric field at optimized driving frequency, the RBCs were trapped in the cavities above the microchannel, whereas the A549 cells were separated with a high capture rate of 86.3% ± 0.2%. The device opens not only the possibility for 3D high‐throughput cell separation but also for future developments in 3D cell manipulation through rapid and low‐cost fabrication.
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- Award ID(s):
- 1917299
- PAR ID:
- 10418941
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ELECTROPHORESIS
- Volume:
- 44
- Issue:
- 23
- ISSN:
- 0173-0835
- Format(s):
- Medium: X Size: p. 1802-1809
- Size(s):
- p. 1802-1809
- Sponsoring Org:
- National Science Foundation
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