TABLE 3.
Main differences between MS methods for MAb analysis
| Main characteristic | MS/MS of proteotypic or clonotypic peptides specific to variable region of MAb with triple-quadrupole mass spectrometera | Intact-protein mass measurement by MS |
||
|---|---|---|---|---|
| MALDI-TOFb | Q-TOFb | Orbitrapb | ||
| Instrument cost | $400,000 | $150,000 | $300,000 | $500,000 |
| Common applications in the clinical lab | Toxicology, endocrinology quantitative assays | Microbiology, bacterial identification | Toxicology drug screening | Mainly present in research labs and esoteric reference laboratories |
| Applications for MAbs | Quantitation of MAbs | Screening of therapeutic MAb | Characterization and quantitation of multiple MAbs | High-resolution characterization and quantitation of multiple MAbs |
a
Labor-intensive, includes reduction, alkylation, and trypsin digestion.
b
Melon Gel enriches for all IgGs. LOQ of MAb quantitation and removal of MAb target should be considered. IgG4 capture is an enrichment option for IgG4 MAbs.