Skip to main content
. Author manuscript; available in PMC: 2014 Oct 1.
Published in final edited form as: Curr Opin Chem Biol. 2013 Jun 18;17(5):10.1016/j.cbpa.2013.05.030. doi: 10.1016/j.cbpa.2013.05.030

Figure 2.

Figure 2

Mass-spectrometry based strategies for quantitation of endogenous peptides. A) Routes of isotope introduction in the stable isotopic labeling methods. B) Overview of select popular chemical labeling methods. C) Typical stable isotopic labeling workflow. D) Label-free quantitation strategies. Key: ICAT–isotope-coded affinity tag; DOTA–1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid; iTRAQ–isobaric tags for relative or absolute quantitation; TMT–tandem mass tags; TMAB–trimethylammoniumbutyryl-based tags; IT-MS–ion trap mass spectrometer; MALDI-TOF–matrix-assisted laser desorption/ionization time-of-flight mass spectrometer.