基于雾化提取和正负离子切换PTR-MS技术高灵敏快速检测水体中VOCs的方法研究

Real-time and on-line detection of trace volatile organic compounds (VOCs) in water is very important to studies of existence, transfer and transformation of trace VOCs in ambient water. However, there isn’t one method for VOCs detection in water with both high sensitivity and high time resolution at present. The development of the atomization-extraction method (AE) and proton transfer reaction mass spectrometry (PTR-MS) presents a potential for real-time, on-line and sensitive detection of VOCs. In this project, we will develop a atomization-extraction-proton transfer reaction mass spectrometry (AE-PTR-MS), with switchable H3O+ and OH- reagent ions, as a new method for VOCs detection in water. The VOCs in water can be extracted by AE, and the extracted VOCs can be detected by PTR-MS. The aromatic compounds in ambient water will be the focus of this project. Atomization-extraction through direct spray and ultrasonic atomization will be studied to improve the effect of atomization. Effects of temperature and salinity on extraction efficiency of aromatic compounds, and effects of humidity on PTR-MS will be studied to accomplish real-time, on-line and sensitive detection of VOCs in water. This project is expected to present a potential for real-time, on-line and sensitive detection of VOCs in ambient water. It will be meaningful for research of ecological environment and environmental protection.

实时在线检测水体中痕量挥发性有机物（VOCs），对于研究环境水体中痕量VOCs的存在、迁移和转化规律等具有重要意义，目前，水体中VOCs在线检测方法难以同时达到快速和高灵敏检测。本项目将从超声雾化和直接加压喷雾两种雾化技术出发，通过雾化提取水体中VOCs，采用H3O+和OH-正负反应离子协同检测的质子转移反应质谱技术（PTR-MS），对提取的VOCs进行高灵敏快速检测，发展雾化提取-质子转移反应质谱（AE-PTR-MS）高灵敏快速检测水体中VOCs的新方法。以水体中苯系物为例，研究两种雾化方式中影响提取效率和速度的因素、水体温度/盐度与喷雾提取效率的关系、高湿气体的除湿和PTR-MS检测、以及环境水体中VOCs检测方法验证和完善。项目预期成果将为环境水体中痕量VOCs高灵敏快速检测提供一种途径，对我国生态环境研究和保护等以及应对水污染突发事件具有重要意义。

项目针对环境水体中痕量VOCs在线检测方法难以同时达到快速和高灵敏的不足，在前期PTR-MS基础上，开展了快速雾化装置研制及喷雾测试研究、加压喷雾提取有机物质谱检测方法研究、超声喷雾提取有机物质谱检测方法研究、双极性质子转移反应质谱研究，并利用新建的质谱装置对实际水样、体液等样品进行检测研究，发展了基于雾化提取-质子转移反应质谱的环境水体中痕量VOCs在线检测方法，实现了对环境水体中痕量VOCs实时在线和高灵敏检测的项目目标。液体中有机物又快又灵敏检测的文章都发表在分析化学和环境科学领域的TOP期刊上。双极性质子转移反应质谱研究工作发表在质谱类顶级期刊上，并且国际同行引用文章并评价这是“Milestone in the development of the PTR-MS technique”；基于双极性质子转移反应质谱技术转化开发的质谱装置已被环保部门采购，该仪器已为安徽省环境科学研究院开展了近3年的24小时不间断的环境VOCs业务化监测任务，取得了一定的社会效益和经济效益。