Understanding the core principles of mass spectrometry

The above refers to a so-called sector instrument, which is a class of MS utilizing a static electric or magnetic sector (or combination of the two) as a mass 

Electron impact (El) On applying a beam of electtons to a biomolecule in a vacuum, the biomolecule loses or gains electrons and is thus ionized. 

East atom bombardment (EAB) On applying a high-energy beam of argon (or zenon) to a biomolecule, it becomes volatile and ionizes. 

Plasma desorption ionization (PDI) On applying a plasma beam to a biomolecule, it strips atomic nuclei of their electrons, causing ionization. 

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