Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Caltech scientists develop 'barcode chip' for cheap, fast blood tests

28.11.2008
A new "barcode chip" developed by researchers at the California Institute of Technology (Caltech) promises to revolutionize diagnostic medical testing. In less than 10 minutes, and using just a pinprick's worth of blood, the chip can measure the concentrations of dozens of proteins, including those that herald the presence of diseases like cancer and heart disease.

The device, known as the Integrated Blood-Barcode Chip, or IBBC, was developed by a group of Caltech researchers led by James R. Heath, the Elizabeth W. Gilloon Professor and professor of chemistry, along with postdoctoral scholar Rong Fan and graduate student Ophir Vermesh, and by Leroy Hood, president of the Institute for Systems Biology in Seattle, Washington.

An IBBC, described in a paper in the advance online edition of Nature Biotechnology, is about the size of a microscope slide and is made out of a glass substrate covered with silicone rubber. The chip's surface is molded to contain a microfluidics circuit--a system of microscopic channels through which the pinprick of blood is introduced, protein-rich blood plasma is separated from whole blood, and a panel of protein biomarkers is measured from the plasma.

The chip offers a significant improvement over the cost and speed of standard laboratory tests to analyze proteins in the blood. In traditional tests, one or more vials of blood are removed from a patient's arm and taken to a laboratory, where the blood is centrifuged to separate whole blood cells from the plasma. The plasma is then assayed for specific proteins. "The process is labor intensive, and even if the person doing the testing hurries, the tests will still take a few hours to complete," says Heath. A kit to test for a single diagnostic protein costs about $50.

"We wanted to dramatically lower the cost of such measurements, by orders of magnitude," he says. "We measure many proteins for the cost of one. Furthermore, if you reduce the time it takes for the test, the test is cheaper, since time is money. With our barcode chip, we can go from pinprick to results in less than 10 minutes."

A single chip can simultaneously test the blood from eight patients, and each test measures many proteins at once. The researchers reported on devices that could measure a dozen proteins from a fingerprick of blood, and their current assays are designed for significantly more proteins. "We are aiming to measure 100 proteins per fingerprick within a year or so. It's a pretty enabling technology," Heath says.

To perform the assay, a drop of blood is added to the IBBC's inlet, and then a slight pressure is applied, which forces the blood through a channel. As the blood flows, plasma is skimmed into narrow channels that branch off from the main channel. This part of the chip is designed as if it were a network of resistors, which optimizes plasma separation.

The plasma then flows across the "barcodes." The barcodes consist of a series of lines, each 20 micrometers across and patterned with a different antibody that allows it to capture a specific protein from the plasma passing over. When the barcode is "developed," the individual bars emit a red fluorescent glow, whose brightness depends upon the amount of protein captured.

In the Nature Biotechnology paper, the researchers used the chip to measure variations in the concentration of human chorionic gonadotropin (hCG), the hormone produced during pregnancy. "The concentration of this protein increases by about 100,000-fold as a woman goes through the pregnancy cycle, and we wanted to show that we could capture that whole concentration range through a single test," Heath says.

The scientists also used the barcode chip to analyze the blood of breast and prostate cancer patients for a number of proteins that serve as biomarkers for disease. The types and concentrations of the proteins vary from disease to disease and between different individuals. A woman with breast cancer, for example, will produce a different suite of biomarkers than will a man with prostate cancer, while a woman with an aggressive form of cancer may produce proteins that are different from a woman with a less-deadly cancer.

Those proteins can also change as a patient receives therapy. Thus, determining these biomarker profiles can allow doctors to create individualized treatment plans for their patients and improve outcomes. The ease and the speed with which results can be obtained using the IBBC also will potentially allow doctors to assess their patients' responses to drugs and to monitor how those responses evolve with time, much as a diabetic patient might use a blood glucose test to monitor insulin delivery.

The barcode chip is now being tested in human clinical trials on patients with glioblastoma, a common and aggressive form of brain tumor. The researchers are also using the chips in studies of healthy individuals, to determine how diet and exercise change the composition of the proteins in the blood.

Currently, the barcoded information is "read" with a common laboratory scanner that is also used for gene and protein expression studies. "But it should be very easy to design something like a supermarket UPC scanner to read the information," making the process even more user-friendly, says Fan, the first author on the paper.

"As personalized medicine develops, measurements of large panels of protein biomarkers are going to become important, but they are also going to have to be done very cheaply," Heath says. "It is our hope that these IBBCs will enable such inexpensive and multiplexed measurements."

Kathy Svitil | EurekAlert!
Further information:
http://www.caltech.edu
http://pr.caltech.edu/media

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>