This post is also available in: heעברית (Hebrew)

Scientists are developing new methods to reveal traces of drugs and bomb-making components. A rather new approach named spectroscopy and in particular, infrared absorption spectroscopy, is used by scientists to detect performance-enhancing drugs in blood samples and tiny particles of explosives in the air. While the method has improved greatly in the last 100 years, researchers are still working to make the technology more sensitive, inexpensive and versatile.

A new light-trapping sensor, developed by a University of Buffalo-led team of engineers, makes progress in all three areas. “This new optical device has the potential to improve our abilities to detect all sorts of biological and chemical samples,” Qiaoqiang Gan, PhD., associate professor of electrical engineering in the School of Engineering and Applied Sciences at UB told the University’s site.

The sensor works with light in the mid-infrared band of the electromagnetic spectrum. This part of the spectrum is used usually for remote controls, night-vision and other applications.

The sensor consists of two layers of metal with an insulator sandwiched in between. Using a fabrication technique called atomic layer deposition, researchers created a device with gaps less than five nanometers between two metal layers. The gaps enable the sensor to absorb up to 81 percent of infrared light, a significant improvement from the 3 percent that similar devices absorb.

The device ,SEIRA is a great advancement and could be useful in any scenario that calls for finding traces of molecules, says Ji, the first author and a PhD. candidate in Gan’s lab. This includes, but is not limited to, drug detection in blood, bomb-making materials, fraudulent art and tracking diseases. Researchers plan to continue the research, and examine how to combine the SEIRA advancement.

The research is supported by the U.S. National Science Foundation’s Nanomanufacturing program, the National Science Foundation of China and the Chinese Scholarship Council.