A label-free mass spectrometry method for the quantification of protein isotypes.

ABSTRACT: Successful quantitative mass spectrometry (MS) requires strategies to link the mass spectrometer response to the analyte abundance, with the response being dependent on more factors than just analyte abundance. Label-dependent strategies rely on the incorporation of an isotopically labeled internal standard into the sample. Current label-free strategies (performed without internal standards) are useful for analyzing samples that are unsuitable for isotopic labeling but are less accurate. Here we describe a label-free technique applicable to analysis of products from related genes (isotypes). This approach enables the invariant tryptic peptide sequences within the family to serve as "built-in" internal standards and the isotype-specific peptide sequences to report the amount of the various

SUBMITTER: Winefield RD 

PROVIDER: S-EPMC3711517 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature