Spectrometers tandem mass

Magnetic sectors can be used on their own, or in conjunction with energy analysers to fomi a tandem mass spectrometer. The unique features of the reverse geometry instrument are presented from this point. 

A single magnetic sector can be used as a mass filter for other apparatus. However, much more infonnation of the simple mass spectrum of a species can be obtained using the tandem mass spectrometer. 

Aside from the smgle mass filter, the most connnon configuration for quadnipole mass spectrometers is the triple-quadnipole instrument. This is the simplest tandem mass spectrometer using quadnipole mass filters. Typically, the... 

Tandem mass spectrometers most commonly used for MS/MS smdies include the following analyzer combinations, although many others are possible ... 

A significant recent experimental advance is the introduction of tandem mass spectrometers for studying ion-molecule reactions. Examining various isotope effects as a function of translational energy can provide detailed information about reaction mechanisms. Tandem experiments can also observe many of the possible reaction channels for a given collision complex. Such information provides valuable clues to the chemical and physical nature of the intermediates in ion-neutral interactions. 

Medzihradszky, K.F., Campbell, J.M., Baldwin, M.A., Falick, A.M., Juhasz, P., Vestal, M.L., and Burlingame, A.L., The characteristics of peptide collision-induced dissociation using a high-performance MALDI-TOF/TOF tandem mass spectrometer, Anal. Chem., 72, 552, 2000. 

Figure 6.19 Schematic of a CID tandem mass spectrometer where MSI and MS2 are the mass analysers, M,1 is the parent or projectile ion, F+ are fragment ions of M,1 generated in the ion source, and F+ are fragment ions formed as a result of CID...

A most suitable tandem mass spectrometer should ... 

Figure 2.3. A. Mass spectrometer consisting of an ionization source, a mass analyzer and an ion detector. The mass analyzer shown is a time-of -flight (TOF) mass spectrometer. Mass-to-charge (m/z) ratios are determined hy measuring the amount of time it takes an ion to reach the detector. B. Tandem mass spectrometer consisting of an ion source, a first mass analyzer, a collision cell, a second mass analyzer and a detector. The first mass analyzer is used to choose a particular peptide ion to send to the collision cell where the peptide is fragmented. The mass of the spectrum of fragments is determined in the second mass analyzer and is diagnostic of the amino acid sequence of the peptide. Figure adapted from Yates III (2000).

Fox, A. Krahmer, M. Harrelson, D. Monitoring muramic acid in air (after alditol acetate derivatization) using a gas chromatography-ion trap tandem mass spectrometer. J. Microbiol. Meth. 1996, 27,129-138. 

Warscheid, B. Jackson, K. Sutton, C. Fenselau, C. MALDI analysis of Bacilli in spore mixtures by applying a quadrupole ion trap time-of-fhght tandem mass spectrometer. Anal. Chem. 2003, 75, 5608-5617. 

There exist essentially three categories of SCX/RP/MS/MS approaches. In one approach, SCX is run off-line followed by on-line RP/MS/MS (Fig. 11.1). In the offline SCX approach, fractions do not directly elute onto RP material but rather are collected. In one of the two in-line approaches, SCX is run in line with RP/MS/MS using different columns for SCX and RP (Fig. 11.2). In the multidimensional protein identification technology approach (MudPIT), SCX and RP are run in line in the same column, and this column serves as the ion source for a tandem mass spectrometer (Fig. 11.3). Both the in-line approaches are true SCX/RP/MS/MS approaches the first approach could be abbreviated as SCX—RP/MS/MS where... 

QqLIT-MS-MS Quadrupole linear ion trap tandem mass spectrometer... 

Shimma S, Furuta M, Ichimura K. A novel approach to in situ proteome analysis using a chemical inkjet printing technology and MALDI-QIT-TOF tandem mass spectrometer. J. Mass. Spectrom. Soc. Jpn. 2006 54 133-140. 

Determination of trace levels of tributyltin residues in sediments can be accomplished by solvent extraction, dilution and FIA (flow injection analysis) into the ionspray of a tandem mass spectrometer, using the 179/291 m/z pair LOD 0.2 p-g Sn/g103. 

Using the Tomtec Quadra 96 workstation, 0.1 mL of the ethyl acetate layer was transferred to a 96-well collection plate containing 0.4 mL of acetonitrile in each sample well. The solution was mixed 10 times by aspiration and dispersion on the Tomtec. The plate was then covered with a sealing mat and stored at 2 to 8°C until LC/MS/MS analysis. The HILIC-MS/MS system consisted of a Shimadzu 10ADVP HPLC system and Perkin Elmer Sciex API 3000 and 4000 tandem mass spectrometers operating in the positive ESI mode. The analytical column was Betasil silica (5 fim, 50 x 3 mm) and a mobile phase of acetonitrile water formic acid with a linear gradient elution from 95 5 0.1 to 73.5 26.5 0.1 was used for 2 min. The flow rate was 1.0 mL/min for the API 3000 and 1.5 mL/min for the API 4000 without any eluent split. The injection volume was 10 jjL and a run time of 2.75 min was employed. 

Kuhlenbeck D.L. et al., 2005. Online solid phase extraction using the Prospekt-2 coupled with a liquid chroma-tography/tandem mass spectrometer for the determination of dextromethorphan, detrophan and quai-fenesin in human plasma. Eur J Mass Spectrom 11 199. 

K. F. Medzihradszky, J. M. Campbell, M. A. Baldwin, A. M. Falick, P. Juhasz, M. L. Vestal, and A. L. Burlingame. The Characteristics of Peptide Collision-Induced Dissociation Using a High-Performance MALDI-TOF/TOF Tandem Mass Spectrometer. Anal. Chem., 72(2000) 552-558. 

Low Mass Region. All spectra shown in the examples were acquired using the quadmpole ion trap mass spectrometer. As noted previously, this widely used and relatively cheap mass analyzer suffers the low-mass cut-off phenomena. In addition to techniques used in the examples shown above, other mass analyzers applied for tandem mass spectrometers may cover the low mass region of the fragmentation spectmm that can be information rich. 

R. S. Johnson, S. A. Martin, K. Biemann, J. T. Stults, and J. T. Watson, Novel Fragmentation Process of Peptides by Collision-Induced Decomposition in a Tandem Mass Spectrometer Differentiation of Leucine and Isoleucine. Anal. Chem., 59(1987) 2621-2625. 

B. Warscheid, K. Jackson, C. Sutton, and C. Fenselau. MALDI Analysis of Bacilli in Spore Mixtures by Applying a Quadrupole Ion Trap Time-of-Flight Tandem Mass Spectrometer. Anal. Chem., 75(2003) 5608-5617. 

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