Technical Aspects and Fragmentation Rules

TABLE 6.3. Types of Ions Formed in Different Types of Instruments 

Source From http //www.matrixscience.com/help/search field help.html, with permission. Abbreviations Q—quadrupole, FT—ion trap, ECD—electron capture dissociation. 

TABLE 6.4. Amino Acids or their Combinations of Similar Molecular Weights, Difficult to Distinguish in Low Resolution Spectra 

High accuracy of the measurements is of utmost importance. There are 20 natural amino acids that, except for the Leu/Ile pair, have different molecular weights. However, the some of them or of some of their combinations have very similar molecular weights. The case of combinations of amino acids with similar molecular weights is especially important when the spectrum lacks a full string of ion peaks (Table 6.4). 

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