A light-trapping sensor, developed by researchers at the University at Buffalo, shows some promise in the detection of performance-enhancing drugs and airborne particles of explosives. Traditionally, detecting drugs, bomb components, and a variety of chemicals often involves shining a light on the materials of interest. Called spectroscopy, this involves observation of how light interacts with trace amounts of matter.
An effective type of spectroscopy is infrared absorption spectroscopy, an approach that has improved over time, but need to be more sensitive, less expensive, and more versatile. The light-trapping sensor from the University at Buffalo is said to meet those requirements. It works with light in the mid-infrared band of the electromagnetic spectrum, a part of the spectrum used for consumer remote controls.
The sensor uses two layers of metal with an insulator in between. Via atomic layer deposition, the device exhibits gaps that are less than 5 nm between the two metal layers. The gaps allow the sensor to absorb up to 81% of infrared light.
The process is known as surface-enhanced infrared absorption (SEIRA) spectroscopy. The sensor, which acts as a substrate for the materials being examined, boosts the sensitivity of SEIRA devices to detect molecules at 100 to 1,000 times greater resolution than previous results. The increase makes SEIRA spectroscopy comparable to another type of spectroscopic analysis, surface-enhanced Rama spectroscopy (SERS), which measures light scattering as opposed to absorbed.
The SEIRA advancement could be useful in any scenario that calls for finding traces of molecules, including drug detection in blood, bomb-making materials, fraudulent art, tracking diseases, and a great deal more. Researchers plan to continue the research, and examine how to combine the SEIRA advancement with cutting-edge SERS. Learn more about this research from a study authored by the researchers.