近日，我所快速分离与检测课题组（102组）李海洋研究团队在痕量爆炸物检测方面取得新进展：基于大气压离子聚焦技术，利用可快速切换极性的离子迁移谱实现了传统含硝基类爆炸物和新型过氧化类爆炸物的单次同时检测，该成果已发表在Nature子刊Scientific Reports上（http://www.nature.com/srep/2015/150529/srep10659/full/srep10659.html）。

离子迁移谱（IMS）是一种常用的爆炸物检测技术，全世界已有20万余台离子迁移谱仪被用于机场安检中的爆炸物筛查。由于化学性质的差异，传统含硝基类爆炸物的检测通常由负离子IMS完成，新型过氧化类爆炸物的检测则由正离子IMS完成。然而，在实际的爆炸物筛查中，传统的离子迁移谱仪仅有一种工作极性，无法完成这两种爆炸物的单次同时检测。李海洋研究团队开发了一种可快速切换极性的离子聚焦离子迁移谱，单次检测即可获得样品的正、负离子谱图信息，成功地实现了10 ng 2,4,6-三硝基甲苯（含硝基类爆炸物）和50 ng 六亚甲基三过氧化二胺（过氧化类爆炸物）的单次同时检测，检测周期小于14 s。同时，该技术保持了对无机炸药主成分（硫磺、硝酸钾、高氯酸钾）的高灵敏检测。

该新型的离子迁移谱拓宽了爆炸物的检测种类，降低了爆炸物的漏检率，在机场、地铁等公共场所的安检中具有广阔的应用前景。

New development in the technique for trace explosive detection

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 explosive detection. 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 above simultaneously. Haiyang Li’s group developed a fast polarity-switchable ion focusing ion mobility spectrometry for explosive detection. With the new technique, 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.