Capture of circulating tumor cells from blood on modified gold surfaces inside the microfluidic channels

Download

index.pdf

Date

2019

Author

Çetin, Didem

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

242
views

130
downloads

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 protein expressing MCF-7 breast cancer cells. Cell binding events were monitored using fluorescent microscopy and antibody attachments through covalent binding and bioaffinity analyzed on different alkanethiol and polyethylene glycol (PEG) thiol SAM formations. The comparison between techniques was made considering the length and functional end of SAMs, homogeneous surface coverage, elimination of the nonspecific binding, positioning of the antibody and steric hindrance effect. Surface characterizations of SAMs and antibody attached surfaces were performed with X-ray Photoelectron Spectroscopy, Atomic Force Microscopy, and contact angle measurements. The selectivity to EpCAM protein was tested with K562 leukaemia cells. The experiments were repeated for other possible microfluidic surfaces, such as glass and polymer. Results obtained from the comparisons are found useful for improvement on the antibody immobilization techniques for CTC capture on biosensor designs

Subject Keywords

Cells., Circulating Tumor Cells, Surface Modification, EpCAM Antibody, Gold Surface, Microfluidic Systems.

URI

http://etd.lib.metu.edu.tr/upload/12624430/index.pdf
https://hdl.handle.net/11511/44752

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Label-free enrichment of MCF7 breast cancer cells from leukocytes using continuous flow dielectrophoresis Arslan, Zeynep Caglayan; Yalcin, Yagmur Demircan; Külah, Haluk (2022-04-01) 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 in...
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...
Capture of rare circulating tumor cells from blood on bio-activated oxide surface inside microfluidic channels Ateş, Hatice Ceren; Külah, Haluk; Özgür, Ebru; Department of Micro and Nanotechnology (2018) Isolation and characterization of circulating tumor cells (CTCs) have important clinical significance in terms of prognosis and early detection of response to treatment. Moreover, downstream characterization of CTCs may help better patient stratification and therapy guidance. However, CTCs are extremely rare (~10 CTCs/1010 peripheral blood cells) and highly sensitive, and specific technology is required for their isolation. Rapidly developing microfluidic technologies offer variety of advantages in rare cel...
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....
Capture and release of viable CTCs in microfluidic channel Ateş, Hatice Ceren; Şen Doğan, Begüm; Özgür, Ebru; Külah, Haluk (null; 2017-10-04) The number of circulating tumor cells (CTCs) in blood is associated with prognosis in several types of cancer. Isolation and characterization of CTCs have important clinical significance in terms of prognosis and early detection of response to treatment. Moreover, downstream characterization of CTCs may help better patient stratification and therapy guidance. However, CTCs are extremely rare and highly sensitive and specific technology is required to isolate viable CTCs from blood cells. In this study, a su...

Citation Formats

D. Çetin, “Capture of circulating tumor cells from blood on modified gold surfaces inside the microfluidic channels,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Biomedical Engineering., Middle East Technical University, 2019.