Aerosols mass spectrometry

Aerosol mass spectrometry (AMS) is used to monitor the chemical composition of particulate matter in the atmosphere. Commercial AMS instruments can provide size and chemical mass loading data on aerosol particles in real time [176]. Such instruments integrate sampling and MS analysis sub-systems. They can be installed permanently or used as components of mobile laboratories [176]. Both quadrupole and TOF AMS devices can provide quantitative data on the chemical composition of volatile/semi-volatile submicrometer aerosols [177]. Importantly, AMS can provide non-refractory aerosol mass 

In one study, AMS was used to investigate the impact of wood combustion on ambient aerosols [181]. Temporal variations of the wood combustion organic aerosol during a 

Mobile mass spectrometers are being developed with transient-concentration measurement capabilities. Temporal resolution of these devices is sufficient to resolve kinetic rates of adsorption of important air pollutants such as exhausts of diesel engines [185]. It is expected that the next few years will bring further miniaturization of mass spectrometers designed for chemical analysis of air in real time, which will enhance the existing environmental monitoring infrastructure. 

A schematic representation of the Aerodyne AMS is shown in Fig. 6.2. The instrument has three main sections the aerosol inlet (particle inlet), the particle sizing 

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Czerwieniec, G. A. Russell, S. C. Tobias, H. J. Fergenson, D. P. Steele, P Pitesky, M. E. Horn, J. M. Frank, M. Gard, E. E. Lebrilla, C. B. Stable isotope labeling of entire Bacillus atrophaeus spores and vegetative cells using bio-aerosol mass spectrometry. Anal. Chem. 2005, 77,1081-1087. 

Today I am going to speak about some of the continuous aerosol mass spectrometry methods that are currently in use. These methods are primarily used for atmospheric chemistry measurements related to human health such as pollution remediation, although now national security and homeland defense applications are starting to evolve. Most aerosol analysis methods are not realtime analyses bridging the gap between on-line and off-line technologies is a challenge that is being addressed. 

Lanz VA, Prevot ASH, Alfarra MR, Weimer S, Mohr C, DeCarlo PF, Gianini MFD, Hueglin C, Schneider J, Favez O, D Anna B, George C, Baltensperger U (2010) Characterization of aerosol chemical composition with aerosol mass spectrometry in central Europe an overview. Atmos Chem Phys 10 10453-10471. doi 10.5194/acp-10-10453-2010... 

Rodgers et al. [85] identified soil surface-bound polycyclic aromatic hydrocarbons through the use of real-time aerosol mass spectrometry in two NIST standard research material soils (Montana SRM 2710 and Peruvian SRM 4355), each contaminated separately with three common petroleum hydrocarbons (diesel fuel, gasoline and kerosene). This method required no sample preparation. Direct laser desorption/ionisation mass spectrometric analysis of individual soil particles contaminated with each of the petroleum hydrocarbons at three different contamination levels (0.8,8, and 80 ppth (wt/wt)) yielded detectable polycyclic aromatic hydrocarbon cation distributions that ranged from m/z 128 to 234, depending on the fuel contaminant. The same analysis... 

Kane DB, Johnston MV (2000) Size and composition biases on the detection of individual ultrafine particles by aerosol mass spectrometry. Environ Sci Technol 34 4887-4893 Ka rcher B, Turco RP, Yu F, Danilin MY, Weisensdn DK, Miake-Lye RC, Busen R (2000) A unified model for ultrafine aircraft particle emissions. J Geophys Res 105 29379-29386 Kashchiev D (1982) On the relation between nucleation work, nucleus size, and nucleation rate. J Chem Phys 76 5098-5102... 

Rodgers, R. P., Lazar, A. C., Reilly, P. T. A., Whitten, W. B., and Ramsey, J. M., Direct determination of soil surface-bound polycyclic aromatic hydrocarbons in petroleum-contaminated soils by real-time aerosol mass spectrometry. Anal. Chem., 72, 5040-5046, 2000. 

Oktem, B., Tolocka, M. P., and Johnston, M. V., On-line analysis of organic components in fine and ultrafine particles by photoionization aerosol mass spectrometry. Anal. Chem., 76, 253-261, 2004. 

Noble CA and Prather KA (2000) Real-time single particle mass spectrometry a historical review of a quarter century of the chemical analysis of aerosols. Mass Spectrometry Reviews 19 248-274. 

In response to this need, aerosol mass spectrometry has developed rapidly and it is now possible to determine both the size (over a limited size range) and qualitative chemical composition of most gas-phase aerosols, with a response time of less than 1 s (see Suess and Prather (1999)). Most of the instruments described in the literature use laser ablation and ionization of the aerosol particles to characterize their chemical composition, but other methods, including thermal vaporization with electron impact ionization, are also used. Here, we first briefly sketch the development of instruments based on laser ablation/ ionization techniques and then describe some of the work that has been done using an aerosol TOP mass spectrometer. 

Reents WD, Schabel MJ. 2001. Measurement of individual particle atomic composition by aerosol mass spectrometry . Anal. Chem. 73(22) 5403-5414. 

K. R., Riot, V, Steele, P.T., Frank, M., Gard, E.E. (2005) Improved sensitivity and mass range in time-of-flight bio-aerosol mass spectrometry using an electrostatic ion guide. Journal of the American Society for Mass Spectrometry, 16, 1866-1875. 

Martin, A.N., Farquar, G.R., Frank, M., Gard, E.E., Fergenson, D.R (2007) Single-particle aerosol mass spectrometry for the detection and identification of chemical warfare agent simulants. Analytical Chemistry, 79, 6368-6375. 

Hildebrandt L, Henry KM, Kroll JH, Worsnop DR, Pandis SN, Donahue NM (2011) Evaluating the mixing of organic aerosol components using high-resolution aerosol mass spectrometry. Environ Sci Technol 45(15) 6329-6335... 

Zhang Q, Alfarra MR, Worsnop DR, Allan JD, Coe H, Canagaratna MR, Jimenez JL (2005) Deconvolution and quantification of hydrocarbon-like and oxygenated organic aerosols based on aerosol mass spectrometry. Environ Sci Technol 39(13) 4938 952... 

Ng NL, Canagaratna MR, Zhang Q, Jimenez JL, Tian J, Ulbrich IM, Kroll JH, Docherty KS, Chhabra PS, Bahreini R, Murphy SM, Seinfeld JH, Hildebrandt L, Drmahue NM, DeCarlo PF, Lanz VA, Prevot ASH, Dinar E, Rudich Y, Worsnop DR (2010) Organic aerosol components observed in northern hemispheric datasets from aerosol mass spectrometry. Atmos Chem Phys 10(10) 4625 641. doi 10.5194/acp-10-4625-2010... 

Figure 5.1 Time evoiution of a.-pinene and pinonaldehyde (resulting from the photooxidation of oi-pinene) as measured by PTR-MS in a reaction chamber experiment. Also shown is the corresponding secondary organic aerosol (SOA) growth curve, as measured by aerosol mass spectrometry. Reproduced with permission from [194]. Copyright 2006, American Chemical Society.

Zhang, Q., M.R. Alfarra, D.R. Worsnop, J.D. Allan, H. Coe, M.R. Canagarama, and J.L. Jimenez (2005), Deconvolntion and qnantification of hydrocarbon-hke and oxygenated organic aerosols based on aerosol mass spectrometry. Environ. Sci. TechnoL, 39, 4938-4952. 

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