Fragment search

Description

This method identifies fragment peaks using MS/MS scan data. Fragment ions are usually produced from another, bigger ion, in the ionization source. Such additional signals represent an undesired noise.

Fragments are identified by 2 conditions: 1) the retention time of the original ion and the fragment ion should be same and 2) the MS/MS pattern of the original ion must be found in the data set and is must contain a peak with the same mass as the fragment ion.

Method parameters

RT tolerance
Maximum allowed retention time difference to set a relationship between peaks
m/z tolerance of MS2 data
Tolerance value of the m/z difference between peaks in MS/MS scans
Max fragment peak height
Maximum height of the recognized fragment peak, relative to the main peak
Min MS2 peak height
Minimum absolute intensity of the MS2 fragment peak. Signals below this level will be ignored.