Review of explosive detection methodologies and the emergence of standoff deep UV resonance Raman

Due to terrorist use of explosive devices, intense interest has been directed towards the development of techniques and instrumentation to detect explosives. A number of analytical techniques are currently under investigation for trace explosive detection. Several methods have been successfully commercialized including colorimetric kits, fluorescence quenching sensors, and ion mobility spectrometers that see widespread field use. A key limitation of all currently utilized field techniques is that they require close proximity or physical interaction with the object being analyzed. The ideal trace explosive detection technique would be able to detect trace amounts of explosives from a distance to ensure personnel safety. Laser-based spectroscopies are the only currently viable techniques that can be utilized to sense trace amounts of explosives at standoff distances. This review compares currently used explosive detection techniques with recently developed standoff methods. We emphasize the development of UV resonance Raman spectroscopy for standoff explosive detection. This work has recently been enabled by advances in laser and spectrometer design. Trace explosive detection has also been advanced by the recently developed understanding of deep UV photochemistry for several explosive molecules. Copyright (c) 2016 John Wiley & Sons, Ltd.