Using Nanosensors to Detect Cancer

Reported December 15, 2009

(Ivanhoe Newswire) -- Doctors are now able to use nanosensors to measure cancer biomarkers in whole blood, which could dramatically simplify the way physicians test for cancer and other diseases.

The team of Yale University researchers, led by Mark Reed, Harold Hodgkinson Professor of Engineering & Applied Science, and Tarek Fahmy, associate professor of biomedical and chemical engineering, used nanowire sensors to detect and measure concentrations of two specific biomarkers, one for prostate cancer and the other for breast cancer.

"Nanosensors have been around for the past decade, but they only worked in controlled, laboratory settings," Reed was quoted as saying. "This is the first time we've been able to use them with whole blood, which is a complicated solution containing proteins and ions and other things that affect detection."

To overcome the challenge of whole blood detection, the researchers developed a device that acts as a filter to catch the biomarkers -- in this case, antigens specific to prostate and breast cancer -- on a chip while washing away the rest of the blood. Creating a buildup of the antigens on the chip allows for detection down to extremely small concentrations, the equivalent of being able to detect the concentration of a single grain of salt dissolved in a swimming pool.

"This new method is much more precise in reading out concentrations, and is much less dependent on the individual operator's interpretation," Fahmy was quoted as saying.

In addition to relying on somewhat subjective interpretations, current tests are also labor intensive and results take several days. In comparison, the new device is able to read out biomarker concentrations in a just a few minutes. "Doctors could have these small, portable devices in their offices and get nearly instant readings," Fahmy said. "They could also carry them into the field and test patients on site."

The new device could be used to test for a wide range of biomarkers at the same time, from ovarian cancer to cardiovascular disease, said Reed. "The advantage of this technology is that it takes the same effort to make a million devices as it does to make just one. We've brought the power of modern microelectronics to cancer detection."

SOURCE: Nature Nanotechnology, December 13, 2009