Patent ID: 9048074
Filing Date: 2015-06-02
Classification: G01N,G16B,H01J

Abstract:
1. A method for analyzing isobarically-labeled analyte compounds using a mass spectrometer, the method comprising the steps of: (a) ionizing a set of compounds including the isobarically-labeled analyte compounds provided from a sample so as to generate a plurality of precursor ion species comprising different respective mass-to-charge (m/z) ratios; (b) isolating a selected precursor ion species; (c) fragmenting the selected precursor ion species so as to generate a plurality of first-generation fragment ion species comprising different respective m/z ratios; (d) selecting and co-isolating a subset of the plurality of first-generation product ion species comprising two or more of the first-generation product ion species; (e) fragmenting the selected and isolated first-generation product ion species so as to generate a plurality of second-generation fragment ion species including released label ions; (f) generating a mass spectrum of the second-generation fragment ion species; and (g) generating quantitative information relating to at least one analyte compound based on peaks of the mass spectrum attributable to the released label ions.