C-MALDI

Carbohydrates are very difficult compounds to analyze using CE because of their inherent structural complexity, frequent lack of a charge and lack of a UV or fluorescent chromophore. They thus require derivatization to facilitate ion formation and detection. 

Despite the number of sheathless CE-ESI interfaces described, few have been used for the analysis of complex carbohydrate mixtures. Zamfir et al. described a sheathless on-line CE/ESI-MS interface consisting of a CE capillary with the terminus shaped into a copper-coated microsprayer.134,135 This was described as 

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Fenselau, C. MALDI MS and strategies for protein analysis. Anal. Chem. 1997, 69, 661A-665A. 

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. 

Ayorinde, F.O. Elhilo, E. Hlongwane, C. MALDI-TOF-MS of Canola, Castor and Olive Oils. Rapid Commun. Mass Spectrom. 1999,75, 737-739. 

Figure 9.25 Tracer studies on tau protein (a) ID gel, (b) 65Cu/63Cu isotope ratios in gel bands measured by LA-ICP-MS, (c) MALDI-FTICR mass spectrum of splice isoform tau F (). Su. Becker, M. Zoriy, M. Przybylski, ]. S. Becker, ]. Anal. At. Spectrom., 22, 63 (2007). Reproduced by permission of the Royal Society of Chemistry.)...

Figure 16.18—FAB and MALDI techniques, a) Principle of fast-atom generation using xenon b) formation of a fast-atom beam of argon in a collision chamber and bombardment of the sample (using a FAB gun) c) MALDI. The impact of a photon leads to a similar result as with a fast atom. The mechanism for desorption ionisation is not entirely known. These ionisation modes are particularly well suited for the study of medium to high molecular weight species. They are mostly used in biomedical sciences but not for routine determinations.

Figure 12.9. (a) Optical images, (b) radioautographic images, and (c) MALDI-MS/MS images from study rat brain tissue section (Hsieh et al., 2006a). 

Figure 1. Mass spectra of a tryptic peptide from the heavy chain of monoclonal andb y CEA11.H5. A. ESI spectrum showing the doubly charged (655.6) and single charged (1310.6) ions. B. LSIMS spectrum for HPLCfiacdtm 50 (m/z 1310.1). C. MALDI spectrum for die same firacdon (m/z 1310,2258,2906, and 4118). An external standard was used far calibration (bovine insulin).

C. MALDI Time-of-Flight Mass Spectrometer (MALDI-TOF-MS)... 

FIGURE 4.5 The five mass spectrometers commonly used for proteomic research, (a) ESI triple-stage quadrupole mass spectrometer (b) ESI quadrupole ion trap (QIT) mass spectrometer (c) MALDI time-of-flight mass spectrometer. 

Figure 16.20 FAB and MALDI techniques, (a) The principle of fast-atom beam formation with xenon (b) The formation of fast atoms of argon in a collision chamber and subsequent bombardment of the sample by this atom beam, usually of 5-10 kV kinetic energy (c) MALDI or ionization by effect of illumination with a beam of laser generated light onto a matrix containing a small proportion of analyte. The impact of the photon is comparable with that of a heavy atom. Through a mechanism, as yet not fuUy elucidated, desorption and photoionization of the molecules is produced. These modes of ionization by laser firing are particularly useful for the study of high molecular weight compounds, especially in biochemistry, though not for routine measurements.

Lattimer, R. R, Poke, M. J., and Wesdemiotis, C., MALDI-MS Analysis of Pyrolysis Products from a Segmented Polyurethane, /. Anal. Appl. Pyrolysis, 48, 15, 1998. 

Calderaro A, Piccolo G, Montecchini S, Buttrini M, Gorrini C, Rossi S, Arcangeletti MC, De Conto F, Medici MC, Chezzi C. MALDI-TOF ms analysis of human and animal Brachyspira species and benefits of database extension. J. Proteomics. 2013 78 273-80. 

Alispahic M, Christensen H, Bisgaard M, Hess M, Hess C. MALDI-TOF mass spectrometry confirms difficulties in separating species of the Avibacterium genus. Avian Pathol. 2014 43(3) 258-63. 

FIGURE 13.6 MALDI imaging ion mobility MS analysis of exogenous pharmaceutieals. (a) A 2D conformation plot of MALDI IM-MS analysis of the drug propranolol (m/z 260, structure shown). Since CID was performed after ion mobility separation, fragment ions eor-relate to the drift time of the parent ion. (From L. S. Fenn, and J. A. McLean. Anal. Bioanal. Chem. 391(3), 905-909, 2008. With permission.) (b) MALDI IMS of vinblastine (VLB, m/z 811). (c) MALDI IMS performed using an SRM strategy to monitor the intensity of the transition m/z 811 751. The incorrect representation of VLB located to the kidney is due to an... 

Fig. 34.3 (a) Coig-calixarene complexes 1 and 2 (b) x-ray crystal structure of 1 [14] (c) MALDI-TOF mass spectrum of 2 [15]. Mode peak analysis corresponds with oligomers of decarbonylated 2, presumably generated by condensation in the gas phase (Reprinted with permissions from the Royal Society of Chemistry and the American Chemical Society)... 

Figure 3.14 Continued) (c) MALDI of the final PEK product bearing barbiturates at both chain ends according to Petraru et al. (2004). (Reprinted with permission from L. Petraru, D. Famik, R. Saf, W.H. Binder, Supramolecular, telechelic poly(etherketones) bearing barbituric acid as hydrogen bonding unit, Polymer Preprints, 45, 2, 690-691, 2004. 2004 Division of Polymer Chemistry, Inc. of the American Chemical Society.) (d) Synthesis of telechelic PCLs with hydrogen bonds via azide-alkine click reactions.

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