Lab-on-Chip Technique Uses Laser-Etched Paper Strips

Lab-on-chips are said to be the future of clinical diagnostics. While the technology is still not yet commercially available, researchers are already improving on it to make it even more portable and affordable.
Researchers at Purdue University have accomplished this by replacing the glass or plastic found in lab-on-chip devices with inexpensive paper. In this fashion, you place a specific reagent on one end of a laser-etched channel, and at the other end apply the sample to be tested, such as saliva, urine, or blood. The reagent moves up the channel through capillary action, and when it hits the sample will react with it and turn a certain color that can indicate a positive/negative result, or indicate the severity of a disease.
At a TEDxBoston conference in 2009, Harvard chemistry professor George Whitesides spoke about a similar concept, although without the laser-etched channels. Purdue researchers claim that their method is simpler:

Our process is much easier because we just use a laser to create patterns on paper you can purchase commercially and it is already impregnated with hydrophobic material,” Ziaie said. “It’s a one-step process that could be used to manufacture an inexpensive diagnostic tool for the developing world where people can’t afford more expensive analytical technologies.

Article @ Purdue University: New lab-on-chip advance uses low-cost, disposable paper strips…
TED Talk – George Whitesides: A lab the size of a postage stamp…
Images: Top: To demonstrate the new concept, the researchers created paper strips containing arrays of dots dipped in luminol, a chemical that turns fluorescent blue when exposed to blood. Blood was then sprayed on the strips, showing the presence of hemoglobin. Side: Colored water is used to show how liquid wicks along tiny channels formed in paper using a laser, in research to develop a new technology for medical diagnostics and chemical analysis. Silica microparticles were deposited on patterned areas, allowing liquid to diffuse from one end of a channel to the other. (Birck Nanotechnology Center, Purdue University)
Medgadget flashback: Paper-based Diagnostic Microfluidic Devices