Patent ID: 9384951
Filing Date: 2016-07-05
CPC Classification: H01J

Claim Text:
1. A method of mass spectrometry comprising: passing parent or precursor ions from a first sample to a collision, fragmentation or reaction device comprising a Surface Induced Dissociation fragmentation device; repeatedly switching, altering or varying said Surface Induced Dissociation fragmentation device between a first mode wherein at least some of said parent or precursor ions from said first sample are fragmented upon impinging upon a surface to produce fragment or daughter ions and a second mode wherein substantially fewer parent or precursor ions are fragmented; passing parent or precursor ions from a second sample to a collision, fragmentation or reaction device comprising a Surface Induced Dissociation fragmentation device; repeatedly switching, altering or varying said Surface Induced Dissociation fragmentation device between a first mode wherein at least some of said parent or precursor ions from said second sample are fragmented upon impinging upon a surface to produce fragment or daughter ions and a second mode wherein substantially fewer parent or precursor ions are fragmented; automatically determining an intensity of first parent or precursor ions from said first sample which have a first mass to charge ratio; automatically determining an intensity of second parent or precursor ions from said second sample which have said same first mass to charge ratio; and comparing the intensity of said first parent or precursor ions with the intensity of said second parent or precursor ions; wherein if the intensity of said first parent or precursor ions differs from the intensity of said second parent or precursor ions by more than a predetermined amount then either said first parent or precursor ions or said second parent or precursor ions are considered to be parent or precursor ions of interest.