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QconCAT: Internal Standard for Protein Quantification



Kerry M. Bauer, Karen W. Phinney, Illarion V. Turko


Protein quantification based on stable-isotope labeling mass spectrometry (SIL-MS) involves adding known quantities of stable-isotope labeled internal standards into biological samples. The internal standards are analogous to analyte molecules and quantification is achieved by comparing signals from isotope-labeled and analyte molecules. This methodology is broadly applicable to proteomics research, biomarker discovery and validation, and clinical studies; which require accurate and precise protein abundance measurements. One such internal standard platform for protein quantification are concatenated peptides (QconCAT). This paper describes a protocol for the design, expression, characterization, and application of the QconCAT strategy for protein quantification.
Isotope labeling of biomolecules Part A & B
Publisher Info
Methods in Enzymology (Elsevier), Oxford, -1


QconCAT, stable isotope labeling, mass spectrometry, proteomics, protein quantification, protocol


Bauer, K. , Phinney, K. and Turko, I. (2015), QconCAT: Internal Standard for Protein Quantification, Isotope labeling of biomolecules Part A & B, Methods in Enzymology (Elsevier), Oxford, -1, [online], (Accessed June 13, 2024)


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Created October 21, 2015, Updated November 10, 2018