Tandem mass spectroscopy

Giusti, M.M. et al., Electrospray and tandem mass spectroscopy as tools for antho-cyanin characterization, J. Agric. Food Chem., 47, 4657, 1999. 

S. Suwanrumpha, R. B. Freas, Identification of Metabolites of Ampicillin Using Liquid Chromatography/Thermospray Mass Spectrometry and Fast Atom Bombardment Tandem Mass Spectroscopy , Biomed. Environ. Mass Spectrom. 1989, 18, 983-994. 

Chemical/Physical. Atkinson et al. (2000) studied the kinetic and products of the gas-phase reaction of 2-heptanone with OH radicals in purified air at 25 °C and 740 mmHg. A relative rate constant of 1.17 x 10 " cmVmolecule Sec was calculated for this reaction. Reaction products identified by GO, FTIR, and atmospheric pressure ionization tandem mass spectroscopy were (with respective molar yields) formaldehyde, 0.38 acetaldehyde, L0.05 propanal, X0.05 butanal, 0.07 pentanal, 0.09 and molecular weight 175 organic nitrates. 

A major consequence of using regulatory limits based on degradant formation, rather than absolute change of the API level in the drug product, is that it necessitates the application and routine use of very sensitive analytical techniques [ 10]. In addition, the need to resolve both structurally similar, as well as structurally diverse degradants of the API, mandates the use of analytical separation techniques, for example, HPLC, CE, often coupled with highly sensitive detection modes, for example, ultraviolet (UV) spectroscopy, fluorescence (F) spectroscopy, electrochemical detection (EC), mass spectroscopy (MS), tandem mass spectroscopy (MS-MS) and so forth. 

Chen, X.-L. et al.. Direct observation of a series of non-covalent complexes formed by phosphor-ylated flavonoid-protein interactions through electrospray ionization tandem mass spectroscopy. Anal Chim. Acta, 511, 175, 2004. 

Busch, K. L., Cooks, R. G. Analytical applications of tandem mass spectrometry in Tandem Mass Spectroscopy (ed.) McLafferty, F. W., p. 11, New York—Chichester—Brisbane— Toronto—Singapore, John Wiley Sons 1983... 

Agrawal, S., Winnik, B., Buckley, B., Mi, L., Chung, F.-L., and Cook, T. J. (2006). Simultaneous determination of sulforaphane and its major metabolites from biological matrices with liquid chromatography-tandem mass spectroscopy. J. Chromatogr. B Anal. Technol. Biomed. Life Sci. 840 99-107. 

Ayrton, J., Dear, G. J., Leavens, W. J., Mallett, D. N., and Plumb, R. S. (1998b). Use of generic fast gradient liquid chromatography-tandem mass spectroscopy in quantitative bioanalysis. J. Chromatogr. B Biomed. Sci. Appl. 709 243-254. 

Giusti MM, Rodriguez-Saona LE, Griffin D and Wrolstad RE, Electrospray and tandem mass spectroscopy as tools for anthocyanin characterization. J Agric Food Chem 47 4657 1664 (1999). 

Other Avenues for Neonatal Critical Care Monitoring with Tandem Mass Spectroscopy... 

The enantiospecific determination of nimodipine in human plasma could be established by liquid chromatography-tandem mass-spectroscopy [27]. The separation was effected using a 8 pm Chiral OJ MOD column (25 cm x 2 mm i.d.), operated at 35°C with ethanol-n-heptane (1 4) containing 2 mM ammonium acetate as the mobile phase (flow rate of 300 pL/min) and MS detection. Calibration graphs were linear over the range of 0.5-75 ng/mL, with a detection limit of 0.25 ng/mL for each enantiomer. 

Note Tandem mass spectroscopy has become to mean the mass spectrum of a mass spectrum hence, MS/MS. Essentially in MS/MS, mass analysers are coupled together via an interface known as a collision cell. Ions of a selected mass (precursor ions) are... 

Noort et al. (1999) again used pronase to digest human serum albumin that had been incubated with sulfur mustard. The cleavage product, 5-[2-[(hydroxyethyl)thio]ethyl]-Cys-Pro-Phe, was analyzed by micro LC-tandem mass spectroscopy. 

Koeberl DD, Young SP, Gregersen N, Vockiey J, Smith WE, Benjamin DK Jr., et al. Rare disorders of metabolism with elevated butyryl- and isobutyryl-carnitine detected by tandem mass spectroscopy newborn screening. Pediatr Res 2003 7 219-23. 

Ayrton, J. Dear, G.J. Leavens, W.J. Mallet, D.N. Plumb, R.S. Use of Generic Fast Gradient Liquid Chromatography-Tandem Mass Spectroscopy in Quantitative Bioanalysis, J. Chromatogr. B 709,243-254 (1998). 

BBB-permeability-liquid chromatography/mass spectroscopy- (LC/MS) Rapid, generic gradient liquid chromatography/ Chu et al. (2002) tandem mass spectroscopy (LC/MS/MS) assays, designed to accelerate sample analyses, have been developed to keep pace with the productivity of advanced synthetic procedures. In this study, LC/MS/MS was combined with an in vitro, cell-based, BBB model to evaluate the potential of new chemical entities (NCEs) to cross the BBB. This in vitro assay provides the permeability of discovery compounds across a monolayer of a primary culture of BBMEC in a fraction of the time that is required for in vivo studies (brain/plasma concentrations), using only 2 mg of the compound. The results are consistent with in vivo brain/plasma concentration ratio data. 

With large proteins, the determination of the primary sequence and post-translational modifications is most efficiently done after digestion with tiypsin or another protease to generate smaller peptides. In this case, the peptides are first separated by HPLC, most commonly RP-HPLC, and the column eluant is directed into the MS. In this hyphenated method, known as LC-MS or liquid chromatography-tandem mass spectroscopy (LC-MS/MS), the individual peptides are analyzed, allowing the identification of post-translational modification sites. In some cases, there are potentially multiple sites in a single peptide that may be modified. 

Gutteck-Amsler, U. and Rentsch, K. M. Quantification of the aminosteroidal non-depolarizing neuromuscular blocking agents rocuronium and vecuronium in plasma with liquid chromatography-tandem mass spectroscopy. Clin. Chem., 46, 1413-1414 (2000). 

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