Recently, new development in the technique for trace explosive detection was achieved by Haiyang Li’s research group (Rapid Separation and Detection Group, 102 Group ) as following: basing on the ion focusing at atmospheric pressure, the simultaneous detection of nitro-based explosive and peroxided-based explosive in a single measurement was accomplished by a fast polarity-switchable ion mobility spectrometer. This result has been published on the journal named Scientific Reports (http://www.nature.com/srep/2015/150529/srep10659/full/srep10659.html).
Ion mobility spectrometry (IMS) is a key technique for trace explosivedetection. All over the world, more than 200 thousands ion mobility spectrometers are serving in the airports for explosive screening. For the different chemical properties, the detection of traditional nitro-based explosives are normally accomplished by negative IMS, while the new peroxide-based explosives are better to be detected by positive IMS. However, the traditional ion mobility spectrometer used for explosive detection in practice can only work in a sole polarity, making it difficult to detect those two explosive species abovesimultaneously. Haiyang Li’s group developed a fast polarity-switchable ion focusing ion mobility spectrometry for explosive detection. With the newtechnique, both of positive and negative spectra for samples can be obtained in a single measurement. Finally, they carried out the simultaneous detection of 10 ng 2,4,6-trinitrotoluene (nitro-based explosive) and 50 ng 2,4,6-trinitrotoluene (peroxide-based explosive) in a single measurement, with a detection period in 14 s. What is more, this new technique can promise the sensitive detection of main components in inorganic explosives, including KClO4,KNO3 and S.
This new technique broadens the detectable explosive species for IMS, which can reduce the undetected probability during explosive screening and offer the great potential for security services in public places, such as airport and subway station.