Oxidation is one of the major chemical degradation pathways for protein pharmaceuticals. This chemical modification, can occur on the methionine, cysteine, histidine, tryptophan, and tyrosine, and among them methionine is the most susceptible to oxidation due to their high reactivity with various active oxygen species, during production, purification, formulation, transportation, storage and handling of solid and liquid preparations, can be induced by contaminating oxidants, catalyzed by the presence of transition metal ions and induced by light.
Oxidation of Met to the sulfoxide form is of distinct interest and significance in biopharmaceutical industry as it occurs on a wide variety of proteins and often reduces or even eliminates biological activity of the protein therapeutics, causes aggregation, increases immunogenicity and encourages degradation. As a result, monitoring protein oxidation becomes critical in biopharmaceutical industry for manufacturing, characterization, and quality control (QC).
Oxidation of specific amino acid residues in tested proteins, can be detected experimentally with a variety of analytical techniques, like such as amino acid analysis, capillary electrophoresis, HPLC-UV and mass spectrometric analysis. Among the analytical methodologies, Creative Proteomics can provide robust and sensitive LC-MS based characterization service under the Bottom-Up strategy. The target protein would be transformed to free peptides by enzymatic cleavage (different proteases would be utilized for comprehensive coverage of the tested protein), and the generated peptides would be separated with nanoLC, for consequent MS analysis to achieve high sensitivity and peptide identification with accurate mass measurements, through database searching.
Our tech support are experienced to modify and optimize the validated protocols for better performance, case by case. So Creative Proteomics are ready to provide professional assistance to you for the development of protein drugs.