By combining HPAE-PAD analysis with acid hydrolysis and enzymatic digestion of protein glycans, information about the glycan identity as well as terminal carbohydrate linkage isomers can be determined from small amounts of protein.
In this Application Note, an Orbitrap-based mass spectrometer is used for high-confidence analysis of the intact and reduced forms of rituximab (monoclonal antibody), in biopharmaceutical product development and characterization.
The Thermo Scientific™ MAbPac™ Protein A column is a high-performance affinity chromatography column specifically designed for the determination of monoclonal antibody concentration in harvest cell culture. The nonporous, hydrophilic stationary phase enables fast and accurate MAb titer analysis. The ability to collect the IgG fraction during the HPLC analysis allows the analyst to characterize the IgG charge variants using a novel pH gradient approach.
A novel pH gradient method for cation-exchange chromatography is discussed. Linear pH gradient was achieved using a multi-component buffer system containing multiple zwitterionic buffer species with pI values from 6 to 10.