Electro-spray ionization mass

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. 

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). 

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. 

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. 

Molecular ion detected by electro spray ionization-mass spectrometry (ESI-MS) in CH3CN solution. 

Also of interest are models from closely related fields, such as Matrix Assisted Laser Desorption/Ionization (MALDI) and Electro Spray Ionization Mass Spectrometry (ESI-MS). MALDI in particular attracts attention as this technique records the large molecular ion emissions resulting from the localized deposition of energy occurring on laser irradiation of the solid s surface. Indeed, there appear to be many similarities in the recorded emissions from SIMS and MALDI. Examples of areas of interest include processes described within the Cluster-based mechanisms and the pooling mechanism. These along with their applicability to SIMS are discussed in Section 3.3.4.2. 

Electro-Spray Ionization Mass Spectrometry (ESI-MS), also referred to as ES-MS, is a mass spectrometric technique that provides a similar information content to that of MALDI, i.e. is useful in the analysis of macro-molecules. ESI-MS can, however, access a greater mass range because a greater number of multiply charged ions are produced relative to MALDI. These ions are produced by dispersing, via electro-spray, a liquid containing the analyte of interest. Ions formed as a result of solvent evaporation are then directed into a mass spectrometer for molecular identification. No prior sample preparation is needed, and analysis can be carried out in close to atmospheric conditions. 

---