Basic Principles of Tandem Mass Spectrometry

Fundamentals of Contemporary Mass Spectrometry, by Chhabil Dass Copyright 2007 John Wiley Sons, Inc. 

By convention, the mass-selected ion is called the precursor ion (mp+) and its fragments are called product ions [e.g., mi+,m2+,m3+, etc. in reaction (4.1)]. The m species in reaction (4.1) are nentral losses. Because of the incontrovertible link between the precnrsor ion and all of its product ions, the molecular specificity of MS/MS approaches unambiguity. This unique attribute of tandem mass spectrometry is a highly nsefnl featnre that plays a role in the unequivocal identification of a target componnd in real-world samples. 

Tandem mass spectrometry is not restricted to two stages of mass analysis (i.e., MS/MS or MS ) it is also possible to perform multistage MS (i.e., higher-order MS) experiments, abbreviated as MS . These experiments can determine the genealogical relation between a precnrsor and its ionic prodncts. For example, MS indicates three stages of tandem mass spectrometry, which involves mass selection of one of the prodncts, say either mi+,m2 , or m3+, formed from 

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Figure 4.1. Basic principle of tandem mass spectrometry. (Reproduced from C. Dass, Principles and Practice of Biological Mass Spectrometry, Wiley-Interscience, 2001.)...

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