Differentiation and quantification of C1 and C2 C-13-labeled glucose by tandem mass spectrometry

作者：Jiang Wei; Wysocki Vicki H; Dodds Eric D; Miesfeld Roger L; Scaraffia Patricia Y^*

来源：Analytical Biochemistry, 2010, 404(1): 40-44.

DOI：10.1016/j.ab.2010.04.035

• Labeled isotopes
• Ion fragmentation
• Mass spectrometry
• Derivatized glucose
• Multiple reaction monitoring scans

The fragmentation patterns of various C-13-labeled glucose molecules were analyzed by electrospray ionization tandem mass spectrometry. Derivatization of glucose to yield methylglucosamine makes the C-C bond between C1 and C2 a favored cleavage site. This is in contrast to underivatized glucose, which favorably undergoes loss of a fragment containing both C1 and C2. Based on the fragmentation pattern of methylglucoasmine, we developed a method to distinguish and quantify C1 and C2 C-13-labeled glucose by derivatization with methylamine followed by multiple reaction monitoring scans in a Q-trap mass spectrometer. Fragment ion ratios in the tandem mass spectra showed an isotope effect with C-13 or deuterium labeling, so a "correction factor" was introduced to make the quantification more accurate. The current approach can be applied to individually monitor the metabolic origin and fate of Cl and C2 atoms in C-13-labeled glucose. This method provides a new means of quantifying glucose isotopomers in metabolic studies.

• 出版日期2010-9-1