ABSTRACT
After defining the “three S rule” and presenting the concept of signal-to-noise ratio, this chapter describes the main acquisition modes of ions in GC-MS coupling: scanning, selected ion recording (SIR), selected ion monitoring (SIM), selected ion storage (SIS), tandem mass spectrometry (MS/ MS), multiple reaction monitoring (MRM), selected reaction monitoring (SRM), and multistage mass spectroscopy (MSn). These concepts are common to most analyzers and their definitions are valid whether one works with a triple quadrupole or a time-of-flight (TOF) analyzer, for example.
