Molecular weight (MW) determination by LC ESI-MS protein analysis is the golden standard for proteins up to 250 kDa.
- Exact molecular weight of proteins
- Determined by UV-LC ESI-MS.
- Accuracy 10 ppm (+/- 1 Da for 100 kDa protein)
- All peaks in the chromatogram are deconvoluted to provide exact masses of all proteins within each peak
- Finally, comparison of data with theoretical MW of protein
The MW of protein isoforms and correlation with the protein sequence enables detailed understanding of the protein heterogeneity.
Furthermore, the MW of co-eluting proteins and integration of HPLC peak areas allows semi-quantitative analysis of protein contaminants and degradation fragments.
- Detect both protein oxidations and deamidation
- Glycoprofile characterization
- Identify contaminating proteins not well separated by UV-HPLC (coeluting proteins or shoulders etc.)
- Stability study – characterize degradation products
- Drug substance batch comparison
The analysis can be conducted with and without reduction, before and after removal of N-glycans and after enzymatic cleavage into specific sub-units.
- Exact mass of intact mAb
- Reduction and MW determination of heavy and light chain
- Removal of N-glycans and intact mass of deglycosylated forms
- IdeS cleavage and MW determination of sub-units
- Finally, comparison of data with theoretical masses
We also offer a range of other monoclonal antibody characterization services. For example: • Disulfide analysis.• Peptide mapping of antibodies. • De-novo sequencing of antibodies • Glycosylation analysis.