Analysis |
Methods |
Molecular Weight |
Liquid Chromatography-Mass Spectrometry (LC-MS) / Liquid Chromatography/Electrospray Mass Spectrometry (LC/ES-MS) of intact, reduced and N-deglycosylated proteins |
Size Variant Analysis |
LC-MS, Size Exclusion Chromatography-Mass Spectrometry (SEC-MS), Dynamic Light Scattering (DLS), Analytical Ultracentrifugation (AUC), Size Exclusion Chromatography-Multi Angle Light Scattering (SEC-MALS) |
Charge Variant Analysis |
LC-MS, Ion Exchange Chromatography-Mass Spectrometry (IEX-MS) |
Thermal stability (Tm) |
Differential Scanning Calorimeter (DSC) |
Extinction Coefficient |
Amino acid analyzers |
Peptide Mapping |
LC-MS after protease digestion |
Protein Sequence Coverage |
LC-MS after one-three digestion |
N-terminal Sequencing |
LC-MS after digestion, determined by peptide mappingEdman degradation |
C-Terminal Sequencing |
LC-MS after digestion |
Disulfide Bonds |
LC-MS after digestion |
Free Sulfhydryl Groups |
Ellman’s assay |
Amino Acid Oxidation |
LC-MS, Reverse Phase High Performance Liquid Chromatography (RP-HPLC) or Hydrophobic Interaction Chromatography-High Performance Liquid Chromatography (HIC-HPLC) and mass spectrometry (MS) |
Amino Acid Isomerization |
LC-MS after enzymatic cleavage |
Deamidation |
LC-MS after enzymatic cleavage |
N-Terminal Modification |
LC-MS after digestion |
C-Terminal Modification |
LC-MS after digestion |
C-terminal Lysine Clipping |
LC-MS after digestion |
N-glycan Profiling |
LC-MS of released glycans |
N-glycosylation Site |
LC-MS after enzymatic cleavage |
N-glycosylation Site Occupancy |
LC-MS after deglycosylase and protease (trypsin or Asp-N) digestion |
Higher Order Structure |
Circular Dichroism (CD)Infrared Spectrometer (IR) |