System detects threats via vapors
The US Department of Homeland Security/Transportation Security Administration (DHS/TSA) has awarded a $1.3 million contract to SpectraFluidics (Goleta, CA, USA) to enable it to develop and validate a vapor detection system that detects homemade explosives.
SpectraFluidics' patented technology works through the use of amicrofluidic chip that is interrogated by surface-enhanced Raman spectroscopy (SERS).
The microfluidic chip includes microfluidic channels, proprietary on-board sensing elements, and flow controllers. The microfluidic channels on the chip have been designed with a surface that is exposed to the surrounding atmosphere. This provides a high surface-to-volume ratio that allows for selective absorption of certain airborne molecules.
The microfluidic chip is interrogated using a proprietary Raman spectrometer to obtain high-sensitivity spectra of various analytes that are relevant to homeland security.Chemometrics algorithms are used to decompose the Raman spectra and identify specific chemicals that are detected by the sensor.
The company claims that the technology would be an improvement on current methods of detecting trace levels of chemicals, including explosives and other contraband, because of its ability to achieve high sensitivity, and specificity of vapor chemistries in a small footprint device.
-- By Dave Wilson, Senior Editor,Vision Systems Design