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  • Quantitatively Differentiating Antibodies Using Charge-State Manipulation, Collisional Activation, and Ion Mobility-Mass Spectrometry
Title: Quantitatively Differentiating Antibodies Using Charge-State Manipulation, Collisional Activation, and Ion Mobility-Mass Spectrometry
Antibody-based therapeutics continue to expand both in the number of products and in their use in patients. These heterogeneous proteins challenge traditional drug characterization strategies, but ion mobility (IM) and mass spectrometry (MS) approaches have eased the challenge of higher-order structural characterization. Energy-dependent IM-MS, e.g., collision-induced unfolding (CIU), has been demonstrated to be sensitive to subtle differences in structure. In this study, we combine a charge-reduction method, cation-to-anion proton-transfer reactions (CAPTR), with energy-dependent IM-MS and varied solution conditions to probe their combined effects on the gas-phase structures of IgG1κ and IgG4κ from human myeloma. CAPTR paired with MS-only analysis improves the confidence of charge-state assignments and the resolution of the interfering protein species. Collision cross-section distributions were determined for each of the charge-reduced products. Similarity scoring was used to quantitatively compare distributions determined from matched experiments analyzing samples of the two antibodies. Relative to workflows using energy-dependent IM-MS without charge-state manipulation, combining CAPTR and energy-dependent IM-MS enhanced the differentiation of these antibodies. Combined, these results indicate that CAPTR can benefit many aspects of antibody characterization and differentiation.  more » « less
Award ID(s):
2203513 1807382
PAR ID:
10484433
Author(s) / Creator(s):
;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Analytical Chemistry
ISSN:
0003-2700
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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