For the first time, a team led by Yale University researchers has used nanosensors to measure cancer biomarkers in whole blood. The new device is able to read out biomarker concentrations in a just a few minutes. Extremely small concentrations are being measured, the equivalent of detecting a single grain of salt within a swimming pool size volume of liquid.
"The new device could also be used to test for a wide range of biomarkers at the same time, from ovarian cancer to cardiovascular disease, Reed said. Science Daily.
Authors of the paper, "Label-free biomarker detection from whole blood", include Eric Stern, Aleksandar Vacic, Nitin Rajan, Jason Criscione, Jason Park, Mark Reed and Tarek Fahmy (all of Yale University); Bojan Ilic (Cornell University); David Mooney (Harvard University).
Distinct components within the sensor perform purification and detection. A microfluidic purification chip simultaneously captures multiple biomarkers from blood samples and releases them, after washing, into purified buffer for sensing by a silicon nanoribbon detector. This two-stage approach isolates the detector from the complex environment of whole blood, and reduces its minimum required sensitivity by effectively pre-concentrating the biomarkers. Nature Nanotechnology, Dec 13, 2009
A close friend of mine died from pancreatic cancer last year. Last week Patrick Swayze died from pancreatic cancer. Approximately 42,000 people in the U.S. will be diagnosed with pancreatic cancer this year. Nearly all of them will die within a year of its discovery. My friend had less than 3 months. With pancreatic cancer, by the time you supect something is wrong, it is too late.
What is needed is a test to detect cancer early from a urine, saliva, or blood sample. I recently wrote about a Lung cancer breathalyzer test.
A similar approach might work for pancreatic and other types of cancer. Certain small pieces of genetic code called microRNA have been associated with various cancers.
For pancreatic cancer, scientists have cataloged dozens of microRNAs whose levels are different than in healthy samples.
Out of the dozens of choices, researchers at the University of Texas M. D. Anderson Cancer Center picked four microRNAs to measure. Not only did the group detect these microRNAs circulating in the blood, they found their levels were higher in the blood of pancreatic cancer patients compared with healthy control subjects. Their results were published last week in Cancer Prevention Research. Scientific American
MicroRNAs in Blood May be Biomarkers of Pancreatic Cancer National Institue of Health
Courtesy mrjorgen The breath of people who have lung cancer is different than those who don't. For years scientists have been perfecting techniques that determines what exactly is different.
Expensive and complicated tools like gas chromatographs and mass spectrometers were used to identify and measure 42 volatile organic compounds that represent lung cancer biomarkers. Sensors were designed to react to four of these compounds.
Gang Peng of the Israel Institute of Technology in Haifa and colleagues have now developed what they say is an inexpensive, portable sensor technology that can quickly distinguish between the breath of lung cancer patients and healthy people. New York Times
Tiny gold nano size beads were coated with organic compounds that would react with the four lung cancer biomarkers. The particles were deposited as a thin film between two electrodes. The breath of someone with lung cancer reacts with the chemicals in the gold beads, changing their electrical resistance.
Physics World has a more complete explanation of how gold nano beads sense lung cancer.
The abstract of the research paper titled "Diagnosing lung cancer in exhaled breath using gold nanoparticles can be found in Nature Nanotechnology.