Dr. Reddy's Laboratories Limited
METHOD FOR IDENTIFICATION AND ABSOLUTE QUANTIFICATION OF PRODUCT-RELATED IMPURITIES IN A PROTEIN USING HIGH-RESOLUTION MASS SPECTROMETRY

Abstract:

The present invention discloses a method for the identification and absolute quantification of peptide based impurities in a protein/antibody composition using high resolution mass spectrometry. The method utilizes synthetic peptides for plotting a standard calibration curve which is, in turn, used for the absolute quantification of the impurities. In particular, the method is utilized for quantification of signal peptide remnants in heterogeneous unpurified or partially purified protein samples, comprising a complex mixture of proteins, with high sensitivity using unlabeled synthetic peptides.