Mass field-portable

Palausky, M. A. Lammert, S. A. Merriweather, R. Sarver, M. B. Sarver, E. W. A field portable ion trap for the detection of chemical weapons compunds. Proc. 43rd ASMS Conf. on Mass Spectrometry and Allied Topics, Atlanta, GA, 1995. 

Mass spectrometers have been used at some level in all of these types of investigations because of their unsurpassed sensitivity and specificity, their multicomponent analytical capability and, in some cases, their ability to provide precise and accurate isotope ratios. Traditional methods of analysis typically involve the collection of water and sediment samples, or biological specimens, during field expeditions and cmises on research vessels (R/Vs), and subsequent delivery of samples to a shore-based laboratory for mass spectrometric analyses. The recent development of field-portable mass spectrometers, however, has greatly facilitated prompt shipboard analyses. Further adaptation of portable mass spectrometer technology has also led to construction of submersible instruments that can be deployed at depth for in situ measurements. 

A 30-lb field-portable quadrupole ion trap TOF (QitTof) mass spectrometer with an atmospheric photoionization source was constructed [17]. The photoionization source has the ability to choose a narrow-band ionization energy that is sufficiently high to ionize and detect most compounds of interest but low enough to avoid ionization of most common air constituents, such as N2, 02, H20, C02, CO, Ar, etc. Fragmentation is minimal because ionization occurs just above the ionization thresholds, with very little excess energy. The ion trap stores ions from a continuous ionization source followed by pulsed extraction into the TOF mass analyzer. 

The technology of GC-MS can be downsized for field usage and is now commercially available. Inficon (USA) manufactures a field-portable GC-MS, Hapsite. Vapor is withdrawn for 30 s into the Tenax preconcentration system, thermally desorbed into the apolar capillary colmnn with elevated temperature control, and the separated components are finally analyzed by the electron ionization quadrupole mass spectrometer. GB, GD, GA, and HD are detected and identified within 12 min with postulated LOD values of 0.2, 0.5, 8, and 0.3 pg/m (Sekiguchi et al, 2006). Gaseous and weakly volatile (boiling temperature >250°C) CWAs cannot be detected. 

Sekiguchi, H., Matsushita, K., Yamashiro, S., Sano, Y., Seto, Y., Okuda, T., Sato, A. (2006). On-site determination of nerve gases and mustard gas using a field-portable gas chromatography-mass spectrometer. Forensic Toxicol. 24 17-22. 

Microfluidics and miniaturization include the development of small and microscale devices to permit chemical measurements, with the objective of field portability or bedside use. Examples include Raman spectroscopy and mass spectrometry. The category also includes devices that employ small-scale fluidics to provide automated sample processing, chemical reactions, separation, and measurement in devices popularly called lab-on-a-chip. 

Si. The deposition of Si occurs by hydrogen reduction of SiHCls, a gas, to form solid Si. The SiHCls, gaseous intermediates such as SiCl2 and gaseous products such as HCl can aU be measured using the mass spectrometer. (This and other applications as weU as a useful mtorial with pictures of the quadrupole and other parts of the mass spectrometer can be found on the MKS Instruments, Inc. website at www.mksinst.com). Even smaller quadrupole mass analyzer systems are available as field portable gas analyzers quadmpoles in these field portable systems are as small as 0.5 inches in length. 

Smith, A. Jackson Lepage, C.R. Koch, D. Detection of gas-phase chemical warfare agents using field-portable gas chromatography-mass spectrometry systems Instrument and sampUng strategy considerations. Trends Anal. Chem. 2004, 23 (4), 296 306. 

Hendricker AD, Abbas-Hawks C, Basile F, Voorhees KJ, Hadfield TL. Rapid chemotaxonomy of pathogenic bacteria using in situ thermal hydrolysis and methylation as a sample preparation step coupled with a field-portable membrane-inlet quadrupole ion trap mass spectrometer. Int... 

EPA/600/R97/019 (SCAPS-LIF), EPA/600/R97/020 (ROST) Field portable gas chromatograph/ mass spectrometer Bruker-Franzen EM 640 (EPA/600/R-97/I49)... 

Sparkman OD, Bierbaum VM. Focus on field-portable and miniature mass spectrometers. Presentations from the 12th Sanibel conference on mass spectrometry. J Am Soc Mass Spectrom. 2001 12 617-8. 

This technique relies on the formation of ions by various means in a high-vaeuum ehamber, their aeeeleration by an eleetrieal field and subsequent separation by mass/eharge ratio in a magnetie field and the deteetion of eaeh speeies. It ean be used for both inorganic and organic substances, be very sensitive, and be of value in examining mixtures of compounds especially if linked to glc. Usually this is a laboratory technique but portable or transportable models are now available. ... 

In analyses where molecular masses are being matched, more accurate mass measurements provide more reliable matches and identifications.26,65,66 In a reference laboratory the mass accuracy to several decimal points, provided by a Fourier transform ion cyclotron resonance mass analyzer, may be desirable. In field or portable systems there is usually a trade-off in mass accuracy for size and ruggedness. Reliable identifications can be made with moderate mass accuracy, even 1 Da, if a large enough suite of molecular ions is recorded and used to search the database. If both positive ion and negative ion spectra are... 

Technical progress as well as investments in PEMFCs for transportation, stationary, portable, and micro fuel cell applications has been dramatic in recent years. The present view is ophmistic for fuel cell power generation the status is presently at the field trial level, or early commercialization stage, moving into volume commercialization. Although commercially viable, niche PEMFC applicahons exist today, the first commercial mass markets for fuel cells are expected to be for handheld electronic devices, PCs, and other portable devices. 

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