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Structural Elucidation of Chemical and Post-translational Modifications of Monoclonal Antibodies



Wenzhou Li, James L. Kerwin, John E. Schiel, Catherine A. Mouchahoir, Darryl Davis, Andrew Mahan, Sabrina A. Benchaar


Therapeutic monoclonal antibodies (mAbs), a rapidly growing class of therapeutic drugs, present a daunting challenge for structural characterization. They are heterodimers of separate light and heavy chains comprising over 1200 amino acid residues. During cellular production as well as during processing and storage, the primary amino acid sequence may be modified through post-translational or chemical processes, and these modifications can affect biological activity, half-life and immunogenicity. Beginning with basic research and proceeding through the various steps of production and formulation, post-translational and chemical modifications (PTMs) must be discovered, tracked, and evaluated for quality, safety, and efficacy. A brief review of the more common modifications encountered during development is presented, with emphasis on those identified on the reference mAb provided by the National Institute of Standards and Technology (NIST). Current and future promising approaches utilizing mass spectrometric and complementary techniques for structural characterization of mAbs are discussed. Many of the aforementioned techniques were used in the characterization of the NIST mAb Reference Material, the results of which are summarized in this chapter.
Current, State of the Art, and Emerging Technologies for the Analysis of Monoclonal Antibodies
Publisher Info
ACS Publications, Washington, DC


NIST mAb, biopharmaceutical characterization, monoclonal antibody, post-translational modification, peptide mapping, forced degradation


Li, W. , Kerwin, J. , Schiel, J. , Mouchahoir, C. , Davis, D. , Mahan, A. and Benchaar, S. (2015), Structural Elucidation of Chemical and Post-translational Modifications of Monoclonal Antibodies, ACS Publications, Washington, DC, [online], (Accessed June 19, 2024)


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Created October 14, 2015, Updated October 12, 2021