Researchers at UCSB have designed a detector that uses microfluidic nanotechnology to mimic the biological mechanism behind canine scent receptors. The device is both highly sensitive to trace amounts of certain vapor molecules, and able to tell a specific substance apart from similar molecules.
“Dogs are still the gold standard for scent detection of explosives. But like a person, a dog can have a good day or a bad day, get tired or distracted,” said the researcher. “We have developed a device with the same or better sensitivity as a dog’s nose that feeds into a computer to report exactly what kind of molecule it’s detecting.”
Packaged on a fingerprint-sized silicon microchip, the underlying technology combines free-surface microfluidics and surface-enhanced Raman spectroscopy (SERS) to capture and identify molecules. A microscale channel of liquid absorbs and concentrates the molecules by up to six orders of magnitude. Once the vapor molecules are absorbed into the microchannel, they interact with nanoparticles that amplify their spectral signature when excited by laser light. A computer database of spectral signatures identifies what kind of molecule has been captured.
“The device consists of two parts,” explained the researcher. “There’s a microchannel, which is like a tiny river that we use to trap the molecules and present them to the other part, a mini spectrometer powered by a laser that detects them. These microchannels are twenty times smaller than the thickness of a human hair.”
“The technology could be used to detect a very wide variety of molecules,” said the researcher. “The applications could extend to certain disease diagnosis or narcotics detection, to name a few.”
This story is reprinted from material from UC Santa Barbara, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.