Kyle RaffertyBiomedical Engineering

Overview

What are CTC’s? Why is detection important? Older methods of detection

Immunomagnetic beadsFlat silicon substrates

New AdvancementSilicon nanopillar substrate

Sources

CTC’s Circulating Tumor Cells Metastasis Deadly

Cancer becoming biggest killer in world (WHO)Most common death from metastasis

Helpful to know amount in bloodstream Examining cancer metastasisPredicting patient prognosisMonitoring cancer

Previous Methods

Immunomagnetic Beads “Utilizes capture-agent-coated magnetic beads to

immunologically recognize CTCs in the blood, followed by magnetic isolation. However, these bead-based approaches are limited by their low CTC-capture yield and purity.”

Use ferrofluids(microscopic iron particles)/antibodies and magnets to extract

CellSearch

Flat Silicon Substrate1x2 cm silicon chipCoated with streptavidin and anti-EpCAM

(epithelial cell adhesion molecule antibody)

Silicon Nanopillar Substrate Build much like flat silicon

1x2 cm silicon ship Built by lithographic tools used for computer

chips

Difference: NanopillarsDiameter~100-200nm; Length~20um

Also coated with streptavidin and anti-EpCAM (epithelial cell adhesion molecule antibody)

SiNP Substrate cont.

Researchers found maximum cell-capture numbers were at 45 min. incubation timeAs compared to 3-4 hrs for previous method

This is more efficient and therefore would probably

cut costsPBS: Phosphate buffered

Saline. Very common

biological solution.

Diagram: how SiNP works

Diagram: Si vs. SiNP

Future Use

Researchers hope to achieve 84-91% detection

Will allow faster detection of cancer’s Allow Doctor’s to customize treatment

plan Increase early detection and survival

rates

Sources Wang, Shutao. “Three-Dimensional Nanostructured Substrates

toward Efficient Capture of Circulating Tumor Cells.” Angewandte Chemie International Edition 48 (2009): 8970-8973. 26 Jan. 2010. http://www3.interscience.wiley.com/cgi-bin/fulltext/122658940/PDFSTART (impact factor: 10.879)

(2) Berger, Michael. “Nanotechnology trap captures cancer cells in blood.” Nanowerk, Nov. 30 2009. 26 Jan. 2010. http://www.nanowerk.com/spotlight/spotid=13743.php

Wikipedia contributors. "Metastasis." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 23 Jan. 2010. Web. 26 Jan. 2010.

Stobbe, Mike. “Cancer top killer in world by 2010.” The Seattle Times, 10 Dec. 2008. 26 Jan. 2010. http://seattletimes.nwsource.com/html/health/2008489006_cancer10.html