PROVO — Deep in the basement of Brigham Young University's Benson building, amid piles of beakers and a jungle of piping, Debolina Chatterjee sits on a stool staring at a clear plastic rectangle, held delicately between her thumb and forefinger.
When held up to the light, the piece of plastic looks almost like a small, simple computer chip: in the center, a smaller piece of plastic has been attached, and on that piece several tiny lines span the distance between a pair of ball bearing-size holes. The entire thing is no more substantial than a bar of soap, two weeks out of the box.
But small as it may be, the implications of the device could be tremendous. A collaboration between Chatterjee, a Ph.D. candidate in chemistry, professor Adam Woolley and others, the rectangle of plastic is a prototype of a new testing device that could revolutionize the way experts test for contaminants in all sorts of liquids. The idea, Woolley explained, is that a liquid — blood or water, for example — is dropped onto the piece of plastic then travels along the hair-size lines, which are actually tubes.
"The tubes are about the same size as real capillaries in blood vessels," Woolley said.
Researchers can then look at how far through the tubes the liquid travels. From that distance, they can extrapolate information about what chemicals might be present. The process could eventually be used to test for diseases such as cancer or tuberculosis, as well as contaminants in water, among other possible applications. The entire process is fast and cheap and requires no electricity.
By contrast, current testing techniques require doctors and researchers to gather liquid samples, send them to labs and wait for results. That can mean long delays before finding out about diseases, which is costly and problematic in more remote parts of the world. Woolley pointed out, for example, that if someone in a remote area is tested for a disease but has to wait days for the results they may never get the treatment they need.
If researchers can cheaply and quickly diagnose people, on the other hand, they can begin treating them on the spot. Someday, Woolley said, the device he and Chatterjee are developing may make that possible.
"It can be used in places where we don't have a lot of high-tech infrastructure," Chatterjee said.
Woolley also mentioned that the device could be used to conduct tests in places where electricity has gone out, such as parts of the East Coast after Hurricane Sandy.
The idea for the device began when Woolley was reading an article about surfaces and testing molecules. In his mind, he recalled, he began to formulate an early idea for the device, but when he initially suggested it to his students they weren't immediately enthusiastic. Then, later, he pitched it to Chatterjee.
"It was a very challenging thing," Chatterjee said. "We didn't know if it would work or not."
But Chatterjee was excited about the concept and ran with it. That was in 2010, and Chatterjee recalled enthusiastically that by 2011 they were seeing results. Those results have continued and were recently published in the journal Analytical Chemistry.
Woolley went on to explain that the device works when liquids interact with receptors on the inside of the tubes. If a particular molecule is present in the liquid, the tube squeezes shut as the receptors pinch around the molecules.
"If there's a lot of this molecule the capillary tube will squeeze closed faster," Woolley said. "With a low concentration it will go slowly."1 comment on this story
Currently, Woolley and Chatterjee are measuring the spot at which the liquid stops flowing with a ruler, though they envision future production models possibly having built-in markings. Chatterjee said it currently takes about two and a half hours to make one device. Each one also probably costs several dollars to produce. But once the testing stage is over the devices could be mass produced quickly and probably for just a few cents.
"The idea is you could make a whole bunch of these in parallel," Woolley said.
Both Chatterjee and Woolley see the device having a positive impact on the world. Chatterjee, who came to BYU from New Delhi, said she hails from a region where there are diseases everywhere and the new device could eventually contribute to solutions to some of those problems. Woolley agreed, but in the meantime, they plan to keep working.
"There's much more to do in research," Chatterjee said.