Development and Characterization of an Aircraft Aerosol Time-of-Flight Mass Spectrometer

• Published in: Analytical chemistry (Washington) Vol. 81; no. 5; pp. 1792 - 1800
• Main Authors: Pratt, Kerri A, Mayer, Joseph E, Holecek, John C, Moffet, Ryan C, Sanchez, Rene O, Rebotier, Thomas P, Furutani, Hiroshi, Gonin, Marc, Fuhrer, Katrin, Su, Yongxuan, Guazzotti, Sergio, Prather, Kimberly A
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.03.2009
• Subjects: Air pollution; Aircraft; Analysis methods; Analytical chemistry; Applied sciences; Atmospheric aerosols; Atmospheric chemistry; Atmospheric pollution; Chemistry; Climate; Exact sciences and technology; General, instrumentation; Mass spectrometry; Pollution; Spectrometric and optical methods; High resolution; Clouds; Data acquisition; Instrumentation; Ice; Real time; Atmospheric dust; Particle detection; Suspended particle; Time resolution; Atmospheric chemistry; Time of flight method; Aerosols; Polarity; Air pollution; Software; Sampling; Aircraft; Mass spectrometry
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac801942r

Vertical and horizontal profiles of atmospheric aerosols are necessary for understanding the impact of air pollution on regional and global climate. To gain further insight into the size-resolved chemistry of individual atmospheric particles, a smaller aerosol time-of-flight mass spectrometer (ATOFMS) with increased data acquisition capabilities was developed for aircraft-based studies. Compared to previous ATOFMS systems, the new instrument has a faster data acquisition rate with improved ion transmission and mass resolution, as well as reduced physical size and power consumption, all required advances for use in aircraft studies. In addition, real-time source apportionment software allows the immediate identification and classification of individual particles to guide sampling decisions while in the field. The aircraft (A)-ATOFMS was field-tested on the ground during the Study of Organic Aerosols in Riverside, CA (SOAR) and aboard an aircraft during the Ice in Clouds Experiment-Layer Clouds (ICE-L). Initial results from ICE-L represent the first reported aircraft-based single-particle dual-polarity mass spectrometry measurements and provide an increased understanding of particle mixing state as a function of altitude. Improved ion transmission allows for the first single-particle detection of species out to ∼m/z 2000, an important mass range for the detection of biological aerosols and oligomeric species. In addition, high time resolution measurements of single-particle mixing state are demonstrated and shown to be important for airborne studies where particle concentrations and chemistry vary rapidly.