Electro-spray ionization

The use of diisoprop anolamine in the synthesis of the hyperbranched poly-esteramide resins has led to defined molecules according to the predicted structures (Fig. 7) as confirmed by MALDI-TOF (Matrix Assisted Laser Desorption Ionization - Time Of Flight) and ESI (Electro Spray Ionization) mass spectra... 

Vivas, N. et al.. Differentiation of proanthocyanidin tannins from seeds, skins and stems of grapes Vitis vinifera) and heartwood of Quebracho (Schinopsis balansae) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and thioacidolysis/liquid chromatography/electro-spray ionization mass spectrometry. Anal Chim. Acta, 513, 247, 2004. 

ESI tandem MS stands for electro spray ionization mass spectrometry performed in multistage. This technique is conducted based on the production of multiply charged ions from proteins and peptides. In this technique, ionization procedure is carried out within the instrument. Three types of mass analyzers are used individually or in combination. 

ERH equilibrium relative humidity ESI electro spray ionization FAB/MS fast atom bombardment mass spectrometry... 

The stoichiometry of the extracted M(III) complexes differs from that of the above-mentioned BTP ligands in that M L2 complexes (instead of M L3 complexes) have been identified by various techniques (e.g., X-ray crystallography, nuclear magnetic resonance, electro-spray ionization mass-spectrometry, and slope analysis in liquid-liquid extraction). 

The mass spectrometry portion of the analysis was carried out by coupling a Bruker Esquire ion-trap mass spectrometer to the LC-NMR system with a 20 1 splitter. The major portion of the flow was directed to the NMR system while the minor fraction went to the mass spectrometer. The system was plumbed such that the sample reached the mass spectrometer and the UV detector at the same time. In this configuration, it is possible to use the mass spectrometer as an intelligent detector, thus allowing stop-flow experiments to be initiated on the basis of observed molecular ions or daughter ion fragments. Data were acquired with electro-spray ionization (ESI) in the positive-ion mode. 

Fig. 3. Electro spray ionization mass spectrometry of the product generated by recombinant GalNAcT. Spectra were acquired in the negative mode. The molecular weight of globotetraose is 706.8. The ion peak at m/z 705.83 is attributed to the molecular ion M-H] of globotetraose.

Trimethylguanine Dimethyl sulfoxide Electro spray ionization mass... 

Theory of CEC and methodological aspects of the technique are described exhaustively in the literature [1,2,3,4,5] and in this monograph and will not be dealt with here further. In this chapter, the current status of instrumentation for CEC is reviewed. General requirements, solvent delivery, and detection will be dealt with in some detail. Coupling of CEC separation with electro-spray ionization mass spectrometry (ESI MS) is of particular importance and is treated in a separate chapter of this monograph. 

Ling, V., Guzzetta, A.W., Canova-Davis, E., Stults, J. T., Hancock, W. S., Covey, T. R., and Shushan, B. I. (1991). Characterization of the tryptic map of recombinant DNA derived tissue plasminogen activator by high-performance liquid chromatography-electro-spray ionization mass spectrometry. Anal. Chem. 63, 2909-2915. 

Biochemical and Biotechnological Applications of Electro spray Ionization Mass Spectrometry, pp. 21-59 (ed. A.P. Snyder), ACS Symposium Series 619, American Chemical Society, Washington, DC. 

A. Antonopoulos, P. Favetta, W. Helbert, and M. Lafosse, On-line liquid chromatography-electro-spray ionization mass spectrometry for K-carrageenan oligosaccharides with a porous graphitic carbon column, J. Chromatogr. A, 1147 (2007) 37—41. 

ESI-MS/MS Electro spray ionization-tandem mass spectrometry TIS-MS/MS Turbo Ion Spray interface-tandem mass spectrometry EAB-MS Fast atom bombardment-mass spectrometry DCI-MS Desorption chemical ionization-mass spectrometry... 

Mass spectrometers see Chapter 7) coupled with gas and liquid chromatographs (see Chapter 6) afe powerful qualitative and quantitative analytical tools that are widely used to measure hormones. Technical advancements in mass spectrometry have resulted, in the, development of matrix-assisted laser desorption/ioiiizati,6n (MALDI) and electro-spray ionization techiiiques that allow siequencing of peptides and mass determination of piconiole quantities of analytes. 

Wu, S.T., Xia, Y.Q., and Jemal, M., High-field asymmetric waveform ion mobility spectrometry coupled with liquid chromatography/electro spray ionization tandem mass spectrometry (LC/ESI-FAIMS-MS/MS) multi-component bioanalytical method development, performance evaluation and demonstration of the constancy of the compensation voltage with change of mobile phase composition or flow rate, Rapid Commun. Mass Spectrom., 21(22), 3667, 2007. 

B. E. Winger, J. E. Campana. Characterization of combinatorial peptide libraries by electro-spray ionization fourier transform mass spectrometry. Rapid Commun. Mass Spectr. 1996, 10. 1811-1813. 

The techniques of matrix-assisted laser desorption/ ionization-time of flight (MALDI-TOF) and electro-spray/ionization (ESI) have revolutionized biological MS since 1989. All state-of-the-art biochemistry and biology laboratories possess at least one of these ionization techniques and, in general, have access to both of them. Both ionization techniques are applicable to peptides and proteins, DNA and RNA, glycoconjugates, and synthetic polymers. 

ESI-TOF MS Electro-spray ionization time of flight mass spectrometry... 

The encapsulation of small molecules, such as N2, O2, methanol, or acetonitrile in ammonium ion complexed Me-CB [5] in the gas phase, was observed using electro-spray ionization Fourier transform mass spectrometry. " The guest is released in the gas phase upon removing an ammonium ion Mid using 18-crown-6. The rate of guest release depends on the size of the guest molecules. 

Guevremont, R. Purves, R.W., High field asymmetric waveform ion mobility spectrometry-mass spectrometry an investigation of leucine enkephalin ions produced by electro spray ionization, J. Am. Soc. Mass Spectrom. 1999, 10,492-501. 

Chromatography equipment high-performance liquid chromatography (HPLC) and coupled electro-spray ionization mass spectrometer, Jordi PolarPac WAX 10,000A 300 X 7.8 mm column (Alltech, Deerfield, IL), and HiLoad 26/60 Superdex 200 gel filtration column (Amersham Pharmacia Biotech, Piscataway, NJ). 

PIA Analysis by Size Exclusion Chromatography/Electro-Spray Ionization Mass Spectrometry... 

This method employs SEC coupled to electro-spray ionization mass spectrometry (ESI/MS) and can he applied to culture filtrate samples and crude PIA extracts isolated from cell surfaces. The acquisition of ESI mass spectra of PIA in positive ion mode is based on the ionization of groups such as hydroxyl groups on sugar residues, or in the case of deacetylated PIA on already ionized amino groups. On the size exclusion columns used under the specific buffer conditions, PIA elutes earlier and separate from most other molecules, soon after the exclusion volume. 

Belov, M. Nikolaev, E.N. Anderson, G.A. Auberry, K.J. Harkewicz, R. Smith, R.D. Electro spray ionization Fourier transform ion cyclotron resonance mass spectrometry using ion preselection and external accumulation for ultrahigh sensitivity. J. Am. Soc. Mass Spectrom. 2001,12, 38-48. 

Byrdwell WC and Neff WE (2002) Dual parallel electro-spray ionization and atmospheric pressure chemical... 

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