Fast, low cost early cancer detection from a drop of blood

It may soon be possible to test a person for cancer with just a drop of their blood and a small machine. An EPFL team is developing an extremely sensitive, easy-to-use device for detecting the HSP70 protein, which is over-expressed in patients with many types of cancer.
The suitcase-size device is expected to be on the market in 2014. The objective: to make a diagnosis extremely early in the disease process, thereby improving outcomes for patients.
HSP70, a protein indicating stress in the human body, is a biomarker for prostate, colon, esophagus, lung, and brain cancer.
The “Spedoc” device requires only a drop of the patient’s blood. The blood is inserted in a chip that contains many microchannels. Inside each of the microchannels are thousands of tiny circular structures made out of gold, with a particular “anti-body” surface chemistry designed to “trap” HSP70 as the blood flows through the channels.
“Our technique involves shining white light on the microfluidic channels,” says EPFL’s Olivier Martin. “If a protein is caught on a nanostructure, we will observe small changes in wavelength as the light is refracted (showing a change of color), which can be observed with a spectrometer.” This uses surface plasmon resonance, which occurs when the electrons of a metallic nanoparticle oscillate together when they are stimulated by light.
The Spedoc early detection method is fast, non-invasive, and low cost, so it could one day replace costly, slower cancer biomarker detection methods, the researchers say.