Label-free enrichment of MCF7 breast cancer cells from leukocytes using continuous flow dielectrophoresis

Arslan, Zeynep Caglayan
Yalcin, Yagmur Demircan
Külah, Haluk
Circulating tumor cells (CTCs) present in the bloodstream are strongly linked to the invasive behavior of cancer; therefore, their detection holds great significance for monitoring disease progression. Currently available CTC isolation tools are often based on tumor-specific antigen or cell size approaches. However, these techniques are limited due to the lack of a unique and universal marker for CTCs, and the overlapping size between CTCs and regular blood cells. Dielectrophoresis (DEP), governed by the intrinsic dielectric properties of the particles, is a promising marker-free, accurate, fast, and low-cost technique that enables the isolation of CTCs from blood cells. This study presents a continuous flow, antibody-free DEP-based microfluidic device to concentrate MCF7 breast cancer cells, a well-established CTC model, in the presence of leukocytes extracted from human blood samples. The enrichment strategy was determined according to the DEP responses of the corresponding cells, obtained in our previously reported DEP spectrum study. It was based on the positive-DEP integrated with hydrodynamic focusing under continuous flow. In the proposed device, the parylene microchannel with two inlets and outlets was built on top of rectangular and equally spaced isolated planar electrodes rotated certain degree relative to the main flow (13 degrees). The recovery of MCF7 cells mixed with leukocytes was 74%-98% at a frequency of 1 MHz and a magnitude of 10-12 V-pp. Overall, the results revealed that the presented system successfully concentrates MCF7 cancer cells from leukocytes, ultimately verifying our DEP spectrum study, in which the enrichment frequency and separation strategy of the microfluidic system were determined.


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Çetin, Didem; Külah, Haluk; Department of Biomedical Engineering (2019)
Detection of circulating tumor cells (CTCs) from the bloodstream has a critical role in diagnosing and treatment of cancer. However, the number of CTCs in blood compared to other blood cells are extremely rare. In this thesis, various surface modifications strategies for detection of CTCs are studied in order to be used in the microfluidic detection systems. Functionalizing the gold surface with Self Assembled Monolayers (SAMs) used for attaching the EpCAM antibodies, which made possible to immobilize EpCAM...
Enrichment of MCF7 breast cancer cells from leukocytes through continuous flow dielectrophoresis
Çağlayan, Zeynep; Külah, Haluk; Department of Electrical and Electronics Engineering (2018)
Circulating tumor cells (CTCs) are cancerous cells detached from a primary tumor site and enter the bloodstream, causing the development of new tumors in a secondary site. Therefore, their detection in blood is critical to assess the metastatic progression and to guide the line of the therapy. However, the rarity of CTCs in the bloodstream and the lack of suitable detection tool hinders their use as a biomarker in malignancies. Recent advances in microfluidic technologies enabled development of point-of-car...
A comparative study on EpCAM antibody immobilization on gold surfaces and microfluidic channels for the detection of circulating tumor cells
Cetin, Didem; Okan, Meltem; Bat, Erhan; Külah, Haluk (2020-04-01)
Detection of circulating tumor cells (CTCs) from the bloodstream holds great importance to diagnose cancer at early stages. However, CTCs being extremely rare in blood makes them difficult to reach. In this paper, we introduced different surface modification techniques for the enrichment and detection of MCF-7 in microfluidic biosensor applications using gold surface and EpCAM antibody. Mainly, two different mechanisms were employed to immobilize the antibodies; covalent bonding and bioaffinity interaction....
Label-free detection of telomerase activity using guanine electrochemical oxidation signal
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Telomerase is an important biomarker for cancer cells and its activation in 85% of all cancer types confers a clinical diagnostic value. A label-free electrochemical assay based on guanine oxidation signal to measure telomerase activity is described. This developed technology combined with a disposable sensor, carbon graphite electrode (CGE), and differential pulse voltammetry (DPV) was performed by using PCR amplicons with/without telomeric repeats as the guanine oxidation signal observed at +1.0 V measure...
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Tunçay Çağatay, Seda; Erson Bensan, Ayşe Elif; Department of Biology (2014)
Metastasis associated protein 1 (MTA1) is a member of the nuclear remodeling and histone deacetylase (NuRD) complex, which is known to repress the expression of several tumor suppressor genes and has been widely linked to tumor metastasis. 15-lipoxygenase-1 (15-LOX-1) is a lipid metabolizing enzyme that has tumor suppressive properties and is silenced by the NuRD complex in colorectal cancer (CRC). We have previously shown that reexpression of 15-LOX-1 inhibited metastasis in CRC, inhibited the inflammatory...
Citation Formats
Z. C. Arslan, Y. D. Yalcin, and H. Külah, “Label-free enrichment of MCF7 breast cancer cells from leukocytes using continuous flow dielectrophoresis,” ELECTROPHORESIS, pp. 0–0, 2022, Accessed: 00, 2022. [Online]. Available: