Researchers from the University at Buffalo, New York, and Fudan University in China have developed a low-cost chip which can reportedly detect the presence of cocaine in only a few minutes. If all goes according to plan, they hope that it will lead to the development of a portable breathalyzer-style device which could be used by law enforcement to reveal whether or not a person has been using the drug.
The new chip uses an especially engineered nanostructure which traps light at the edges of gold and silver nanoparticles. In the event that biological or chemical molecules land on the chip’s surface, part of this captured light interacts with the new molecules and is “scattered” in recognizable patterns, which can reveal which compound is present. In addition to cocaine, the surface-enhanced Raman spectroscopy (SERS) technology could be used to look for opioids and the active ingredients in marijuana. It is able to uncover even tiny traces of these compounds.
“In practical applications, especially for commercial SERS chips, shelf time is usually an important parameter,” researcher Nan Zhang told Digital Trends, explaining why the technology is so promising. “Due to the fragile nanostructure and stability of metal materials, the claimed shelf time for most commercial SERS chips is relatively short. The performance of SERS chip may degrade over time, especially for silver-based structures. [However, our] proposed SERS substrate was demonstrated effective after a 12-month shelf time in an ambient storage environment.”
Zhang noted that the technology is also low-cost. The sensors could be made for just a few dollars, offering a high level of sensitivity with very little in the way of investment.
“We have already got a Chinese patent for this low-cost developed SERS substrate,” Zhang continued. “We are trying to introduce this product into a broad market once we find a proper investor to cooperate with. It has been recognized that a huge market exists if this price can be reduced down to $1 to $5.”
A paper describing the work, “Superabsorbing Metasurfaces with Hybrid Ag-Au Nanostructures for Surface-Enhanced Raman Spectroscopy Sensing of Drugs and Chemicals,” was recently published in the journal Small Methods.