A comparison of electrospray tandem mass spectra of some derivatives of sialic acid: ion trap and high resolution QqToF mass spectrometers
T13N2
A.O. Chizhov, A.M. Spirt1, N.Y. Savel’eva, L.O. Kononov
Using O-acetyl-N-acyl derivatives of O-methyl sialoside methyl esters it was shown that an ion trap and a hybrid analyzer (linear quadrupole — time-of-flight analyzer, reflectron) give comparable, though not identical secondary order mass spectra for the [M+Na]+ and [M+K]+ ions. A parallel use of an ion trap and a hybrid QqToF instrument makes possible to get information on fragmentation pathways of ions of sialic acid derivatives under collisional activation. In this case, a sequence of fragmentation may be established using an ion trap, whereas a QqToF instrument gives a possibility to reveal elemental composition of fragment ions quickly and unequivocally.
T13N2
Contents
Application of high-performance liquid chromatography / high resolution mass spectrometry for investigation of sodium 2,3-disulfanyl- 1-propanesulfonate (unithiol) and products of its oxidation with hydrogen peroxide
T13N2
D.O. Kuleshov, T.E. Berezkina, Y. V. Russkikh, E. N. Chernova, Z. A. Zhakovskaya,
S.V. Masyukevich, L.N. Gall, N.R. Gall
High-performance liquid chromatography combined with high resolution mass spectrometry has been used to study soft oxidation of sodium 2,3-disulfanyl-1-propanesulfonate (unithiol) with hydrogen peroxide; reference peaks were identified for initial substance and reaction products. The possibility to use high-performance liquid chromatography with high resolution mass spectrometry for Sokolovsky thiol-disulphide test has been shown.
Disentangling of information about the structure of biomolecules based on decomposition and separation of two-dimensional charge distributions of ions
T13N2
V.V. Raznikov, M.O. Raznikova, M.L. Pridatchenko Далее
Detection of metabolites of flavonoids Epimedium in rats urine by high performance liquid chromatography-high-resolution tandem mass spectrometry
T13N2
O.A. Shevlyakova, K.J. Vasil’yev, A.A. Ihalaynen, A.M. Antokhin, V.F. Taranchenko,
V.M. Goncharov, A.V. Aksenov, D.A. Mitrofanov, I.A. Rodin, O.A. Shpigun Далее
Synthesis of ion-optical devices for transportation of charged particle beams in mass spectrometers
T13N2
V.V. Pavlov, N.K. Krasnova Далее
Mass spectrometry of analytical derivatives. 2. “Ortho” and “Para” effects in electron ionization mass spectra of derivatives of hydroxy, mercapto and amino benzoic acids
T13N2
Нино Гурамовна Тодуа, Анзор Иванович Микая
Derivatives requiring either anhydrous or aqueous reaction conditions were prepared for robust and reliable gas chromatography/mass spectrometry (GC/MS) characterization of hydroxyl, mercapto, and amino benzoic acids. Methylation and trialkylsilylation are employed for blocking the acidic function. Alkyl, trimethylsilyl, acetyl, perfluoroacyl and alkoxycarbonyl derivatization groups are introduced to hydroxyl, mercapto and amino functions. The electron ionization induced fragmentation characteristics of corresponding derivatives are explained by comparing the MS1 spectra of unlabeled compounds to their 2H and 13C labeled analogs, and analysis of collision-induced dissociation data from MS2 spectra. Competing fragmentation alternatives are identified and specific decomposition processes are detailed that characterize (a) ortho isomers due to interaction of vicinal functional substituents and (b) para isomers prone to forming para quinoid type structures. Skeletal and hydrogen rearrangements typical for methyl benzoates and the blocking groups are considered when discussing diagnostically important ions. Characteristic ions produced as a result of rearrangements in ortho isomers are classified, and skeletal rearrangements required to produce para quinoid type ions specific for para isomers are noted. Key ions for structure elucidation and differentiation of isomers for derivatives of substituted benzoic acids by GC/MS are suggested.
