title: Fluorogenic tagging methodology applied to characterize oxidized tyrosine and phenylalanine in an immunoglobulin monoclonal antibody.
abstract: OBJECTIVE
  Metal-catalyzed oxidation (MCO) of proteins is of primary concern in the development of biotherapeutics as it represents a prominent degradation pathway with potential undesired biological and biotherapeutic consequences.
  
  
  METHODS
  We developed a fluorogenic derivatization methodology to study the MCO of IgG1 using a model oxidation system, CuCl2/L-ascorbic acid.
  
  
  RESULTS
  Besides the oxidation of Met, Trp and His residues, we detected significant oxidation of Phe and Tyr in IgG1.
  
  
  CONCLUSIONS
  The fluorogenic derivatization method provides an alternative approach for the rapid detection of oxidized Tyr and Phe as their benzoxazole derivatives by fluorescence spectrometry and size exclusion chromatography coupled to fluorescence detection.
authors: Department of Pharmaceutical Chemistry, University of Kansas, 2095 Constant Avenue, Lawrence, Kansas 66047, USA.
authors: Shuxia
authors: S
authors: Zhou
authors: Olivier
authors: O
authors: Mozziconacci
authors: Bruce A
authors: BA
authors: Kerwin
authors: Christian
authors: C
authors: Schöneich
mesh_terms: D001205:Ascorbic Acid / Q000737:chemistry; D001583:Benzoxazoles / Q000032:analysis; D003300:Copper / Q000737:chemistry; D007074:Immunoglobulin G / Q000737:chemistry*; D010084:Oxidation-Reduction; D010649:Phenylalanine / Q000031:analogs & derivatives / Q000032:analysis*; D013050:Spectrometry, Fluorescence / Q000379:methods; D014443:Tyrosine / Q000031:analogs & derivatives / Q000032:analysis*
chemical_list: D001583:Benzoxazoles; D007074:Immunoglobulin G; D014443:Tyrosine; D010649:Phenylalanine; D003300:Copper; D001205:Ascorbic Acid; C029892:cupric chloride