Coupling capillary electrophoresis - mass

Because of the small amounts of sample that are usually obtained, coupled GC-MS is the method of choice for analysis of volatile pheromones. The analysis of the less-volatile lipids and polar pheromone components may require derivatization and microchemical tests, both to improve chromatographic characteristics and to provide information about the structures. It is likely that chromatographic techniques with high separation power and high sensitivity for polar compounds, such as coupled capillary electrophoresis-mass spectrometry, will prove useful for analysis of spider extracts in future studies. 

As in HPLC, the coupling of MS detection with CE has provided an excellent opportunity for more selective analysis, but the much reduced flow rates, small injection volumes, limitations in the types of buffers used [since electrospray ionization (ESI) is used in capillary electrophoresis/mass spectrometry (CE/MS)], and need to... 

Li J, Purves RW, Richards JC. 2004a. Coupling capillary electrophoresis and high-field asymmetric waveform ion mobility spectrometry mass spectrometry for the analysis of complex lipopolysaccharides. Anal Chem 76 4676. 

Liu, C. C., Jong, R., and Covey, T. (2003). Coupling of a large-size capillary column with an electrospray mass spectrometer. A reliable and sensitive sheath flow capillary electrophoresis-mass spectrometry interface.. Chromatogr. A 1013, 9-18. 

Petersson, M. A., Hulthe, G., and Fogelqvist, E. (1999). New sheathless interface for coupling capillary-electrophoresis to electrospray mass-spectrometry evaluated by the analysis of fatty acids and prostaglandins./. Chromatogr. A 854, 141 — 154. 

Capillary electrophoresis mass spectrometry (CE-MS) Direct coupling of capillary electrophoresis (CE) and MS, where the mass spectrometer serves as the detector. Biomolecules are separated through the narrow capillary of the CE system and then interface with the MS for subsequent analysis. 

Capillary Electrophoresis-Mass Spectrometry The first report on coupling capillary electrophoresis with mass spectrometry was published in 1987,-" Since then, it has become obvious that this hyphenated method will become a powerful and important tool in the analysis of large biopolyniers. such as proteins, polypeptides, and DNA species. In most of the applications reported to date, the capillary effluent is passed... 

Settlage, R. E., Russo, P. S., Shabanowitz, J., and Hunt, D. F., A novel /x-ESI source for coupling capillary electrophoresis and mass spectrometry sequence determination of tumor peptides at the attomole level. J. Microcolumn Sep., 10, 281-285, 1998. 

Interfaces for Coupling Capillary Electrophoresis with Mass Spectrometry... 

Figure 6.6 Schematic drawing of commonly used CE-ESi-MS interfacing sheath-flow and sheathless coupling [5], Reproduced from Mischak, H., Coon, j.j., Novak, ]., Weissinger, E.M., Schanstra, ].R, Dominiczak, A.E (2009) Capillary Electrophoresis-Mass Spectrometry as a Powerful Tool in Biomarker Discovery and Clinical Diagnosis an Update of Recent Developments. Mass Spectrom. Rev. 28 703-724 with permission from John Wiley and Sons...

B. Santos, B.M. Simonet, B. Lendl, A. Rios, M. Valcarcel, Alternatives for coupling sequential injection systems to commercial capillary electrophoresis-mass spectrometry equipment, J. Chromatogr. A 1127 (2006) 278-285. 

Michalke, B. (2000). Advantages and improvements in selenium speciation—Improvements in coupling capillary electrophoresis on-line to inductively coupled plasma mass spectrometry are described in the field of selenium speciation. Spectroscopy 15(4), 30. 

Hutton, T. and Major, H.J., Characterizing biomolecnles by electrospray ionization-mass spectrometry coupled to liqnid chromatography and capillary electrophoresis, Biochem. Soc. Trans., 23, 924, 1995. 

In E. Coli bacterial lysates, the proteome (i.e., the full array of proteins produced) was analyzed by isoelectric focusing and mass spectrometry.97 A comparison of capillary electrophoretic separation and slab gel separation of a recombinant monoclonal antibody demonstrated that the precision, robustness, speed, and ease-of-use of CE were superior.98 Seventy-five proteins from the yeast ribosome were analyzed and identified by capillary electrophoresis coupled with MS/MS tandem mass spectrometry.99 Heavy-chain C-terminal variants of the anti-tumor necrosis factor antibody DE7 have been separated on capillary isoelectric focusing.100 Isoforms differing by about 0.1 pi units represented antibodies with 0,1 or 2 C-terminal lysines. 

ESI-MS is the most successful method of coupling a condensed phase separation technique to a mass spectrometer. Because the input to ESI is a liquid, electrospray serves as an interface between the mass spectrometer and liquid chromatographic techniques, including SEC and CE (capillary electrophoresis). In LC-MS the flow-rate should lie in the range recommended for the HPLC pump and the mass spectrometer (typically 0.001 -l.OmLmin-1). Recent advances in (nano)electrospray technology include the development of the use of very low solvent flow-rates (30 to 1000nLmin-1) [130,131],... 

Bergstrom, S.K., Samskog, J., Markides, K.E. (2003). Development of a poly(dimethylsilox-ane) interface for on-line capillary column liquid chromatography-capillary electrophoresis coupled to sheathless electrospray ionization time-of-flight mass spectrometry. Anal. Chem. 75, 5461-5467. 

Parallel to the development of mass spectrometric instrumentation and methodologies, the improvements of separation techniques, such as gas chromatography (GC), high performance liquid chromatography (HPLC) and capillary electrophoresis (CE), and of their coupling with MS allowed the study of complex mixtures, that are generally encountered in most studies. 

Characterization of Organic Natural Dyes by Electrospray Mass Spectrometry Coupled with HPLC and/or Capillary Electrophoresis... 

Identification and quantification of natural dyes need high performance analytical techniques, appropriate for the analysis of materials of complicated matrices containing a small amount of coloured substances. This requirement perfectly fits coupling of modern separation modules (usually high performance liquid chromatography in reversed phase mode, RPLC, but also capillary electrophoresis, CE) with selective detection units (mainly mass spectrometer). 

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