Development of An Instrument for Aerosol and Bacteria Analysis by Laser Desorption FTMS

在主要研究仪器（MRI）项目的支持下，阿肯色大学的Charles Wilkins教授将开发一种最先进的激光解吸傅立叶变换质谱仪（FTMS），用于气溶胶和细菌分析。这种新的分析工具将采用多激光气动尺寸和激光解吸颗粒样品。对于质量分析，将使用3特斯拉离子捕获FTMS。气溶胶源与FTMS的结合将使从单个颗粒中获取尺寸相关的激光解吸质谱数据成为可能，从而允许将化学物质与发现它们的颗粒大小相关联。由于FTMS的捕获特性，使用多级质谱法对未知物质进行结构解析将成为可能。因此，将有可能应用强大的MS/MS结构解析方法，从已知大小的单个颗粒中解吸出物种，从非均匀源实时采样。了解单个气溶胶颗粒的详细化学成分对于理解诸如大气的化学和动力学，如何控制微电子制造设施中的小颗粒污染以及颗粒暴露对健康的影响作为大小的函数等不同主题至关重要。新的气溶胶FTMS将允许高灵敏度-高分辨率的质谱分析颗粒的大小同时确定。还将探讨在细菌和小生物分析方面的潜在应用。在这个项目中研制的仪器也将作为实地便携式仪器的原型，这将使新技术能够应用于广泛的实际分析问题。

With support from the Major Research Instrumentation (MRI) Program, Prof. Charles Wilkins of the University of Arkansas will develop a state-of-the-art laser desorption Fourier-transform mass spectrometer (FTMS) for aerosol and bacteria analysis. This new analytical tool will employ multiple lasers for aerodynamic sizing and laser desorption of particulate samples. For mass analysis, a 3 Tesla ion trapping FTMS will be used. The combination of an aerosol source with FTMS will make possible the acquisition of size-correlated laser desorption mass spectral data from single particles, allowing correlation of chemicals identified with the sizes of particles upon which they are found. Because of the trapping features of the FTMS, structural elucidation of unknowns using multiple stage mass spectrometry will be possible. Thus, it will be possible to apply powerful MS/MS structure elucidation methods to species desorbed from single particles of known sizes, sampled in real time from inhomogeneous sources. Knowledge of the detailed chemical composition of individual aerosol particles is essential for understanding such diverse topics as the chemistry and dynamics of the atmosphere, how to control small particle contamination in microelectronic fabrication facilities, and the health implications of particulate exposure as a function of size. The new aerosol FTMS will allow high sensitivity-high resolution mass spectral analysis of particles with sizes determined simultaneously. Potential applications to bacterial and small organism analysis also will be explored. The instrument developed in this project will also serve as a prototype for field portable versions, which will allow application of the new technology to a wide range of practical analytical problems.