Comprehensive characterization of biotherapeutics is necessary to satisfy safety standards set by regulatory agencies and helps to ensure protein drug efficacy. Intact protein analysis using a combination of liquid chromatography (LC) and mass spectrometry (MS) provides information on the accurate mass of the protein and the relative abundance of its isoforms. The analysis of these complex heterogeneous protein biotherapeutics benefits from high resolution accurate mass (HRAM) instrumentation. Combining HRAM with powerful data deconvolution algorithms facilitates structural confirmation and accurate identification of protein modifications.
Intact mass analysis workflow
Using Orbitrap technology Drug to Antibody Ratio (DAR) analysis can be performed in native conditions, and without the need for deglycosylation. BioPharma Finder software provides automatic determination of DAR values. Performing antibody drug conjugate (ADC) analysis of the unaltered or native ADC mixture allows DAR value calculations to be done based on multiple glycoforms. In the example shown here the average DAR value is calculated using four different glycoforms and is very consistent, providing added information, DAR measurement accuracy and analytical confidence.