Kyle Rafferty Biomedical Engineering

Overview  What are CTC’s?  Why is detection important?  Older methods of detection Immunomagnetic beads Flat silicon substrates  New Advancement Silicon 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 metastasis Predicting patient prognosis Monitoring 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 Substrate 1x2 cm silicon chip Coated 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: Nanopillars Diameter~ nm; 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 time As compared to 3-4 hrs for previous method  This is more efficient and therefore would probably cut costs PBS: 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): Jan bin/fulltext/ /PDFSTART (impact factor: )  (2) Berger, Michael. “Nanotechnology trap captures cancer cells in blood.” Nanowerk, Nov Jan  Wikipedia contributors. "Metastasis." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 23 Jan Web. 26 Jan  Stobbe, Mike. “Cancer top killer in world by 2010.” The Seattle Times, 10 Dec Jan html