Question

In chromatography-MS what are MS1 and MS2 for?

Answer 1

These following scheme explains how Tandem MS works. Once samples are ionized (by ESI, MALDI, EI, etc.) to generate the mixture of ions, precursor ions of a specific mass-to-charge ratio (m/z) are selected called MS1 and then fragmented that said MS2 to generate a product ions for detection.MS1 is simply used as a mass filter, so parallel detection offers no advantage, and a quadrupole mass filter is a good choice because it can be efficiently coupled to the collision cell and a second mass spectrometer (MS2) to analyze the daughter ions produced from breakup of the parent.