激光解吸快速GC-PTR-MS在线检测难挥发有机物研究

Proton transfer reaction mass spectrometer (PTR-MS) has been widely used for rapid monitoring of volatile organic compounds. For a long time, PTR-MS has been facing two great challenges: unable distinguish the substances with the same molecular weight, unable directly detect the organic compounds in solid state. To solve these problems, this project proposes to develop laser desorption fast GC-PTR-MS technique for online detecting nonvolatile organic compound. This method will possess the following novel characteristics: (1) the pulsed laser desorption GC injection can accomplish in situ sample vaporization injection of solid-state nonvolatile organic compounds; (2) by coupled with gas chromatography (GC), the fast GC-PTR-MS can distinguish compounds with same mass, the ion collision-induced dissociation can help identify the molecular composition; (3) the ion focusing drift tube can enhance the detection efficiency and achieve high sensitivity for PTR-MS detection. In situ detection of nonvolatile organic compounds in pesticide residues and chemical product including drugs will be carried out so as to demonstrate its advancement and validity.

质子转移反应质谱PTR-MS被广泛用于挥发性有机物的快速监测。但长期以来，PTR-MS面临着两大科学难题：一是不能直接检测固态有机物，二是不能区分分子量相同的物质。为此，本项目拟开展激光解吸快速GC-PTR-MS在线检测难挥发有机物研究，特色与创新性包括：（1）脉冲激光解吸GC进样，实现对固态难挥发有机物的原位汽化进样；（2）色谱联用形成快速GC-PTR-MS，能分辨分子量相同物质，借助离子碰撞诱导解离，可帮助物质种类定性；（3）离子反应漂移管具有离子聚焦功能，增强离子透过率，保障PTR-MS检测的高灵敏。并开展农药残留、药品等化工产品难挥发物原位检测实验研究，展现新技术方法的先进性和有效性。

质子转移反应质谱PTR-MS被广泛用于挥发性有机物的快速监测，但是，PTR-MS存在着不能检测固态有机物、难以区分分子量相同物质的困难。为此，项目开展了激光解吸快速GC-PTR-MS在线检测难挥发有机物的实验研究：（1）研制的高效离子源产生的反应离子H3O+的强度和纯度分别达到~10^7cps量级和90%。（2）发展了快速GC-PTR-MS检测分析技术，GC分离时间可以到达140s以内，也能区分同分异构体。（3）建立了中红外激光解吸进样GC-PTR-MS装置，实现了对固态物质的气化脉冲进样与检测分析，对四氟菊酯的检测限可以达到1pg。（4）在激光解吸进样GC-PTR-MS装置上，成功地开展了蔬菜食品、药物、农药、乳胶漆、染料、土壤等一系列的检测实验研究。项目发展的中红外激光解吸进样GC-PTR-MS检测技术方法，不但拓展了PTR-MS的适用范围，而且为固态物品中的有机物分析，提供了一种新的检测技术手段。