Dopant-Assisted Negative Photoionization Ion Mobility Spectrometry for Sensitive Detection of Explosives
Dopant-Assisted Negative Photoionization Ion Mobility Spectrometry for Sensitive Detection of Explosives
复制标题
掺杂剂辅助负光电离离子淌度光谱法用于爆炸物的灵敏检测
DOI：
10.1021/ac302836f
复制
发表时间：
2013-01-01
影响因子：
7.4
通讯作者：
Li, Haiyang
中科院分区：
文献类型：
--
作者：
Cheng, Shasha;Dou, Jian;Li, Haiyang
离子迁移率光谱法（IMS）是爆炸物痕量检测的关键技术，开发一种简单、稳定、高效的非放射性电离源是迫切需要的。为IMS开发了一种掺杂剂辅助负光电离（DANP）源，该源使用商用VUV氪灯电离丙酮作为电子源，在空气中产生负反应物离子。以20 ppm的丙酮为掺杂剂，可获得1.35 nA的稳定反应物离子电流。通过大气压飞行时间质谱法鉴定反应物离子为CO3-(H2O)(n) (K-0 = 2.44 cm(2) V-1 s(-1))，而Ni-63源中的反应物离子为O-2(- 2) (H2O)(K-0 = 2.30 cm（2) V-1 s(-1)）。最后，评价了该方法对硝酸铵燃料油（ANFO）、2,4,6-三硝基甲苯（TNT）、硝酸铵（2-羟乙基）胺（DINA）和四硝酸铵季戊四醇（PETN）等常见爆炸物的检测能力，获得了10 pg （ANFO）、80 pg （TNT）和100 pg （DINA）的检出限，线性范围为2个数量级。利用DANP源获得的飞行时间质谱清楚地表明，PETN和DINA可以通过CO3-离子缔合反应直接电离生成PETN。CO3-和DINA。CO3-加合物离子，对DANP源具有良好的灵敏度。其优异的稳定性、良好的灵敏度，特别是较好的分离反应物和产物离子峰的特性，使DANP成为潜在的IMS非放射性电离源。
Ion mobility spectrometry (IMS) is a key trace detection technique for explosives and the development of a simple, stable, and efficient nonradioactive ionization source is highly demanded. A dopant-assisted negative photoionization (DANP) source has been developed for IMS, which uses a commercial VUV krypton lamp to ionize acetone as the source of electrons to produce negative reactant ions in air. With 20 ppm of acetone as the dopant, a stable current of reactant ions of 1.35 nA was achieved. The reactant ions were identified to be CO3-(H2O)(n) (K-0 = 2.44 cm(2) V-1 s(-1)) by atmospheric pressure time-of-flight mass spectrometry, while the reactant ions in Ni-63 source were O-2(-)(H2O) (K-0 = 2.30 cm(2) V-1 s(-1)). Finally, its capabilities for detection of common explosives including ammonium nitrate fuel oil (ANFO), 2,4,6-trinitrotoluene (TNT), N-nitrobis(2-hydroxyethyl)amine dinitrate (DINA), and pentaerythritol tetranitrate (PETN) were evaluated, and the limits of detection of 10 pg (ANFO), 80 pg (TNT), and 100 pg (DINA) with a linear range of 2 orders of magnitude were achieved. The time-of-flight mass spectra obtained with use of DANP source clearly indicated that PETN and DINA can be directly ionized by the ion-association reaction of CO3- to form PETN.CO3- and DINA.CO3- adduct ions, which result in good sensitivity for the DANP source. The excellent stability, good sensitivity, and especially the better separation between the reactant and product ion peaks make the DANP a potential nonradioactive ionization source for IMS.