Regeneron Pharmaceuticals, Inc.
HEAVY PEPTIDE APPROACH TO ACCURATELY MEASURE UNPROCESSED C-TERMINAL LYSINE

Abstract:

The present disclosure provides a method for accurately measuring post-translational modifications in proteins such as antibodies. In particular, the method pertains to the use of heavy isotopic standards to generate a calibration curve to allow for accurate quantitation of a modified peptide. The method may be used to accurately quantify C-terminal truncation in antibodies using mass spectrometry.