A MASS SPECTROMETRIC METHOD OF PEPTIDE QUANTITATION BY LABELING PEPTIDES WITH N-METHYLPIPERAZINE ACETIC ACID AND ITS ISOTOPOLOGUES

摘要

PURPOSE: A peptide quantitation using isotopologues of N-methylpiperazine acetic acid and a mass spectrometer is provided to purify and quantitate peptides with high reliability. CONSTITUTION: A peptide quantitation using N-methyl piperazine acetic acid substitution comprises: a step of treating a test sample with protease to cleave with peptide; a step of preparing isotopologue compounds in which entire or partial C, N, O, or H is substituted with ^13C, ^15N, ^18O or ^2H; a step of treating the cleaved peptide samples with isotopologue compounds for labeling; a step of mixing the labeled peptide samples; a step of scanning the samples using a mass spectrometer; and a step of analyzing MS/MS spectrum. The protease is trypsin.