Mass spectrometry ion trap

Inductively Coupled Plasma Mass Spectrometry Handbook 

Ions are transferred from the atmospheric pressure ICP into the high vacuum chamber of the mass spectrometer via a differential pumping interface. The ions are formed into a beam 

Many variations on ion trap scan functions are known and utilized for all manner of ion manipulation and detection coUisionally induced dissociation (CID), selective ejection or trapping, high mass resolution, ion reaction, chemically selective excitation of motion via the mass shift , etc. The interested reader is referred to the significant ion trap literature already cited. 

The differential equations describing the forces acting on the trapped particles have been developed and discussed in detail. A summarized version of the derivation given by Todd is presented here. The equations of motion are of the form 

The ion trap is a device that utilizes ion path stability of ions for separating them by their m/z [53]. The quadrupole ion trap and the related quadrupole mass filter tvere invented by Paul and Steinwedel [57]. A quadrupole ion trap (QITor 3D-IT) mass spectrometer operates with a three-dimensional quadrupole field. The QIT is formed by three electrodes a ring electrode with a donut shape placed symmetrically between two end cap electrodes (Fig. 1.20). 

By applying a fundamental RF potential, the QIT can be described as a small ion storage device where ions are focused toward the center of the trap by collision with helium gas. In the QIT, because of the cylindrical symmetry of the trap, the x and y components of the field are combined to a single radial r component, where + y. The motion of ions in the trap is characterized by one 

MS trap CID generates similar spectra than quadrupole CID, but there are cases where the spectra differ significantly. 

For molecules which can easily lose water or ammonia, the most abundant fragment observed in MS is M-18 or M-17, which is not very informative. To overcome this limitation, wide band excitation (range 20 m/z units) can be applied. Another difference compared to QqQ is that QIT have a low mass cutoff of about one-third of the mass of the precursor ion. However QIT is particularly attractive to follow fragmentation cascades as illustrated for bosentan in Fig. 1.22. It can clearly be concluded that the fragment at m/z 175 originated from the precursor at 202 and not from the precursor at m/z 311. 

Schwartz et al. [59] described a standalone linear ion trap where mass analysis is performed by ejecting the ions radially through slits of the rods using the mass instability mode. To maximize sensitivity the detection is performed by two detectors placed axially on either side of the rods (see Fig. 1.23). 

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March R E and Todd J F J 1995 Practical Aspects of Ion Trap Mass Spectrometry (Boca Raton, FL Chemical Rubber Company)... 

Son M, Frankevich V, Nappi M, Santini R E, Amy J W and Cooks R G 1996 Broad-band Fourier transform quadrupole ion trap mass spectrometry Anal. Chem. 68 3341 -20... 

IKES. ion kinetic energy spectroscopy IRMS. isotope ratio mass spectrometry ISDMS. isotope dilution mass spectrometry ITMS. ion trap mass spectrometry LA. laser ablation... 

Adams, F., Gijbels, R., and Van Grieken, K., Inorganic Mass Spectrometry, Wiley Interscience, New York, 1988. Adams, R.R, Identification of Essential Oils by Ion Trap Mass Spectrometry, Academic Press, San Diego, CA 1989. 

Martinez Bueno MJM, Agiiera A, Gomez MJ, Hernando MD, Garcia JE, Fernandez-Alba AR (2007) Application of liquid chromatography/quadrupole-linear ion trap mass spectrometry and time-of-flight mass spectrometry to the determination of pharmaceuticals and related contaminants in wastewaters. Anal Chem 79 9372-9384... 

A multi-residue method based on SPE cleanup and gas chromatography/ion trap mass spectrometry (GC/ITMS) was developed for the determination of 120 pesticides and related metabolites in two soils with organic matter contents of 4.0-5.2%. 

Debrauwer, L. Rathahao, E. Jouanin, I. Paris, A. Clodic, G. Molines, H. Convert, O. Fournier, F. Tabet, J. C. Investigation of the regio- and stereoselectivity of deoxygua-nosine linkage to deuterated 2-hydroxyestradiol by using liquid chromatography/ESI-ion trap mass spectrometry. J. Am. Soc. Mass Spectrom. 2003, 14, 364—372. 

Appropriate use of RF and DC voltages means that some ions can be selectively retained and product ions generated. Some of these ions can then be selected and their product ions generated. In this manner, a fragmentation chain can be established. The ion trap is a typical tandem-in-time mass spectrometer, in which precursor and product ions are created and analysed in the same physical space ionisation and ion analysis, on the other hand, take place at different times ( MS/MS in time )- The operation can be repeated several times, making it possible to perform MS11. Ion trap mass spectrometry thus consists of ... 

SFE-GC-MS is particularly useful for (semi)volatile analysis of thermo-labile compounds, which degrade at the higher temperatures used for HS-GC-MS. Vreuls et al. [303] have reported in-vial liquid-liquid extraction with subsequent large-volume on-column injection into GC-MS for the determination of organics in water samples. Automated in-vial LLE-GC-MS requires no sample preparation steps such as filtration or solvent evaporation. On-line SPE-GC-MS has been reported [304], Smart et al. [305] used thermal extraction-gas chromatography-ion trap mass spectrometry (TE-GC-MS) for direct analysis of TLC spots. Scraped-off material was gradually heated, and the analytes were thermally extracted. This thermal desorption method is milder than laser desorption, and allows analysis without extensive decomposition. 

FID = flame ionization detection GC = gas chromatography HPLC = high performance liquid chromatography ITMS = ion trap mass spectrometry MS = mass spectrometry PNMR = proton nuclear magnetic resonance TLC = thin-layer chromatography... 

Buchanan MV, Hettich RL, Xu JH. 1995. Low level detection of chemical agent simulants in meat and milk by ion trap mass spectrometry. Journal of Hazardous Materials 42 49-59. 

Quadrupole Ion Trap Mass Spectrometry. Second Edition. By Raymond E. March and John F. J. Todd... 

Larsson, L. Saraf, A. Use of gas chromatography-ion trap mass spectrometry for the detection and characterization of microorganisms in complex samples. Mol. Biotechnol. 1997, 7, 279-287. 

Smith, P B. Snyder, A. E Characterization of bacteria by quartz tube pyrolysis-gas chromatography/ion trap mass spectrometry. J. Anal. Appl. Pyrolysis 1992, 24, 23-38. 

EPA SW-846 Method 8265, Volatile Organic Compounds in Water, Soil, Soil Gas, and Air by Direct Sampling Ion Trap Mass Spectrometry. Electronic version of EPA SW-846 Manual available at http //www.epa.gov/epaoswer/hazwaste/test/ new-meth.htm 8265. 

Barshick, S. A. Wolf, D. A. Vass, A. A. Differentiation of microorganisms based on pyrolysis ion trap mass spectrometry using chemical ionization. Anal. Chem. 1999,71,633-641. 

Xu, M. Basile, F. Voorhees, K. J. Differentiation and classification of user-specified bacterial groups by in situ thermal hydrolysis and methylation of whole bacterial cells with tert-butyl bromide chemical ionization ion trap mass spectrometry. Anal. Chim. Acta 2000, 418,119-128. 

Jelic A, Petrovic M, Barcelo D (2009) Multi-residue method for trace level determination of pharmaceuticals in solid samples using pressurized liquid extraction followed by liquid chromatography/quadrupole-linear ion trap mass spectrometry. Talanta 80 363-371... 

Kang J, Hick LA and Price WE. 2007. A fragmentation study of isoflavones in negative electrospray ionization by MSn ion trap mass spectrometry and triple quadrupole mass spectrometry. Rapid Commun Mass Spectrom 21 (6) 857—868. 

To detect nitro explosives in seawater Barshick et al. [298] investigated a method based on gas chromatography-ion trap mass spectrometry. 

Complex matrixes typically cannot be analysed directly to obtain the selectivity and sensitivity required for most trace analysis applications. To circumvent this problem, solid-phase micro extraction techniques were used to preconcentrate analytes selectively prior to gas chromatography/ion trap mass spectrometry analysis. 

Guerra P, Eljarrat E, Barcelo D (2008) Enantiomeric specific determination of hexabromo-cyclododecane by liquid chromatography-quadrupole linear ion trap mass spectrometry in sediment samples. J Chromatogr A 1203 81-87... 

Hogenboom A.C., Niessen W.M.A., and Brinkman U.A., 1998. Rapid target analysis of microcontaminanant in water by online single-short-column liquid chromatography combined with atomospheric pressure chemical ionization ion-trap mass spectrometry. J Chromatogr A 794 201. 

MOR were comparable (10 ng mL4), whereas those for DHC and EMOR were about fourfold lower. Furthermore, glucuronides were shown to react like the corresponding free opioids. Validation with real urine samples was performed with identification of the peaks by capillary electrophoresis-ion-trap mass spectrometry (CE-MS) after solid-phase extraction. 

Y. Wang, M. Schubert, A. Ingendohm and J. Franzen. Analysis of Non-Covalent Protein Complexes up to 290 kDa Using Electrospray Ionization and Ion Trap Mass Spectrometry. Rapid Commun. Mass Spectrom., 14(2000) 12-17. 

R. E. March. Quadrupole Ion Trap Mass Spectrometry Theory, Simulation, Recent Developments and Applications. Rapid Commun. Mass Spectrom., 12(1998) 1543-1554. 

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