Mass spectrometry charge exchange

One attempt to overcome these disadvantages has been to use multidimensional liquid chromatography (LC) followed directly by tandem mass spectrometry to separate, fragment and identify proteins (Link et al., 1999). In this process, a denatured and reduced protein mixture is digested with a protease to create a collection of peptides (Fig. 2.6). The peptide mixture is applied to a cation exchange column and a fraction of these peptides are eluted based on charge onto a reverse-phase column. The... 

Holmes, J.L. Mommers, A.A. Terlouw, J.K. Hop, C.E.C.A. The Mass Spectrometry of Neutral Species Produced From Mass-Selected Ions by Collision and by Charge Exchange. Experiments With Tandem Collision Gas Cells. Int. J. Mass Spectrom. Ion Proc. 1986, 68,249-264. 

Deuterium may be analyzed from density measurements of waters. A confirmation method recommended here is GC mass spectrometry. Deuterium is burned in oxygen (or air) to form D2O which may be separated with helium on a GC column (of intermediate polarity) and identified from its mass spectra. The mass to charge ratio of the molecular ion is 20. Additionally, deuterated products obtained by exchange reactions with hydrogen containing substances (other than those containing C—H bonds) may be separated on a capillary GC column and identified by mass spectrometry. 

R. Marx, M. Gerard, T. R. Govers, and G. Mauclaire, Luminescence in Near Thermal Charge Exchange, paper presented at Seventh International Mass Spectrometry Conference, Florence, 1976. 

In these rather special PIPECO experiments, ions are being produced with selected internal energy and their lifetimes are measured. FIK achieves measurement of time, and PIPECO in its usual form and charge exchange fix energy. To both preselect energy and measure time is the desired, yet rare, level of experiment in mass spectrometry. 

Physical properties Charge (see ion-exchange chromatography Chapter 7) Density (see centrifugation Chapter 6) Mass (see mass spectrometry Chapter 9) and Shape (see spectroscopy Chapter 5). 

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