Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Magnetic nanotags allow sensitive detection of cancer biomarkers

 The magnetic nanotag-based protein assay chip has a 200 microliter reaction well and is supported by an 84-pin ceramic base. Embedded in the bottom of the reaction well are 64 sensors in an 8-by-8 array. Credit: Osterfeld et al., PNAS.
The magnetic nanotag-based protein assay chip has a 200 microliter reaction well and is supported by an 84-pin ceramic base. Embedded in the bottom of the reaction well are 64 sensors in an 8-by-8 array. Credit: Osterfeld et al., PNAS.

Abstract:
The detection of cancer-associated proteins, or biomarkers, in blood samples is a potentially powerful tool for early diagnosis of cancer and monitoring of cancer treatment. A team led by researchers at Stanford University and the University of California, Santa Cruz, has developed a compact prototype detector that uses magnetic nanotechnology to spot cancer-associated proteins in a human blood serum sample with much higher sensitivity than current detectors.

Magnetic nanotags allow sensitive detection of cancer biomarkers

Santa Cruz, CA | Posted on December 1st, 2008

The researchers describe their results in a paper published by Proceedings of the National Academy of Sciences (PNAS) the week of December 1, 2008.

In addition to its high sensitivity, the new detector can monitor multiple biomarkers simultaneously. This "multiplex" capability is important because the use of multiple biomarkers is likely to provide greater accuracy and reliability than single biomarkers for cancer diagnosis and other potential applications, said Nader Pourmand, professor of biomolecular engineering at UCSC.

"With current detectors, you can only detect one protein at a time," Pourmand said. "Instead of the standard fluorescent tags, we used nanosized magnetic beads as tags and were able to detect target molecules with tens to hundreds of times greater sensitivity than standard techniques."

"This is essentially a proof-of-concept study showing that now we have a chip and a reader that can find multiple biomarkers in a sample at a concentration much lower than the standard that is commercially available," said Shan Wang, a Stanford professor of materials science and engineering and electrical engineering.

Wang and Pourmand are senior authors of the paper, along with Stanford biochemistry and genetics Professor Ronald W. Davis.

To tag the cancer proteins with magnetic nanoparticles, the detector subjects blood serum samples to an incubation process that takes place in roughly half an hour. At the heart of the detector is a silicon chip designed by the paper's first author, Sebastian Osterfeld, a Stanford materials science and engineering doctoral student. The chips have 64 embedded sensors whose electrical resistance changes in the presence of a nearby magnetic field. Attached to these sensors are capture antibodies that have the unique ability to latch on to specific cancer-related proteins as they float by.

During the incubation process, these antibodies first capture their specific cancer proteins. Next, a second wave of antibodies attach to the specific cancer proteins on one end and magnetic nanoparticles on the other end, tethering the captured cancer biomarkers to magnetic "nanotags." The tags emit a magnetic field that causes a change in the resistance of the underlying sensor, giving the detector a clear signal.

In the PNAS paper, the researchers described detection of very low concentrations of various cancer biomarkers, such as tumor necrosis factor alpha and cancer embryonic antigen. In a multiplex assay involving seven potential cancer biomarkers, concentrations ranging from 5 quadrillionths to 0.1 trillionths of a mole (a standard unit of measurement for molecules) were unambiguously detected simultaneously.

The researchers also estimated that they could detect levels of the protein human chorionic gonadotropin about 400 times lower than the concentration detectable by current commercial kits known by the acronym ELISA, in which captured proteins are conjugated to color-altering or fluorescent labels.

To properly prepare a patient's blood sample for use with the detector, a technician must use a centrifuge to separate out the serum, which contains the biomarkers. For this reason, the device would need to be located in a hospital or a private diagnostic lab, Wang said. Even before that, the device faces clinical utility testing and then must undergo clinical trials to win regulatory approval. To see the device through those steps, Pourmand and Wang have cofounded a startup company, MagArray, in the Panorama Institute for Molecular Medicine, a nonprofit incubator in Sunnyvale, Calif.

Wang said he is optimistic that the technology could someday save lives by detecting cancer early or by helping doctors to select more effective therapy.

"The earlier you can detect a cancer, the better chance you have to kill it," Wang said. "This could be especially helpful for lung cancer, ovarian cancer, and pancreatic cancer, because those cancers are hidden in the body."

The nascent startup has also begun to apply the technology to diagnosis and assessing risk of heart attack in emergency rooms. Heart cell death is also associated with the release of specific biomarker proteins.

The research was funded partly by grants from the U.S. National Institutes of Health, the National Science Foundation, and the Department of Defense. Other authors of the paper include Heng Yu, Richard Gaster, Stefano Caramuta, Liang Xu, Shu-Jen Han, Drew Hall, Robert Wilson, and Robert White, all of Stanford, and Shouheng Sun, of Brown University.

####

For more information, please click here

Contacts:
Pourmand
(831) 502-7315


Tim Stephens
(831) 459-2495

Copyright © UC Santa Cruz

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

JPK announces expansion of its global sales and service activities in China and USA April 15th, 2014

Nanobiotix Appoints Thierry Otin as Head of Manufacturing and Supply April 15th, 2014

PAM-XIAMEN Offers UV LED wafer April 15th, 2014

Engineers develop new materials for hydrogen storage April 15th, 2014

Chip Technology

Scientists open door to better solar cells, superconductors and hard-drives: Research enhances understanding of materials interfaces April 14th, 2014

Obducat has launched a new generation of SINDRE® Nano Imprint production system April 11th, 2014

Scientists in Singapore develop novel ultra-fast electrical circuits using light-generated tunneling currents April 10th, 2014

Clean Shot at Manufacturing Course…For Less April 9th, 2014

Nanomedicine

Nanobiotix Appoints Thierry Otin as Head of Manufacturing and Supply April 15th, 2014

PAM-XIAMEN Offers UV LED wafer April 15th, 2014

Nanocrystalline cellulose modified into an efficient viral inhibitor April 15th, 2014

Targeting cancer with a triple threat: MIT chemists design nanoparticles that can deliver three cancer drugs at a time April 15th, 2014

Discoveries

Engineers develop new materials for hydrogen storage April 15th, 2014

Nanocrystalline cellulose modified into an efficient viral inhibitor April 15th, 2014

Tiny particles could help verify goods: Chemical engineers hope smartphone-readable microparticles could crack down on counterfeiting April 15th, 2014

A molecular approach to solar power: Switchable material could harness the power of the sun — even when it’s not shining April 15th, 2014

Announcements

Tiny particles could help verify goods: Chemical engineers hope smartphone-readable microparticles could crack down on counterfeiting April 15th, 2014

A molecular approach to solar power: Switchable material could harness the power of the sun — even when it’s not shining April 15th, 2014

Targeting cancer with a triple threat: MIT chemists design nanoparticles that can deliver three cancer drugs at a time April 15th, 2014

Biologists Develop Nanosensors to Visualize Movements and Distribution of Plant Stress Hormone April 15th, 2014

NanoNews-Digest
The latest news from around the world, FREE







  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE