Resolving ADC Complexity with Subunit-Level Mass Spectrometry:​ Characterization and Beyond

September 7, 2026

Antibody-drug conjugates (ADCs) combine the specificity of monoclonal antibodies with potent payloads, but variable drug loading, conjugation-site heterogeneity, glycosylation, post-translational modifications, and clipping create a complex mixture of molecular species. While intact mass analysis provides an important overview, subunit-level analysis can reveal chain-specific details needed for more comprehensive characterization and subsequent monitoring of ADC product quality attributes. 

This poster presents a subunit-level mass spectrometry workflow in Genedata Expressionist^® that uses time-resolved deconvolution to characterize ADC heterogeneity while preserving retention-time information. You will learn how automated processing supports the identification of subunit variants and low-abundance clipped species, distinguishes conjugation-site isomers, and enables rapid and consistent calculation of drug-to-antibody ratio and payload distribution with minimal manual processing. The poster also demonstrates how identified product quality attributes can be transferred from in-depth characterization into robust, scalable routine monitoring using deconvoluted extracted ion chromatograms, extending the multi-attribute monitoring concept from peptide mapping to the intact subunit level. Designed for scientists working in ADC characterization, product quality assessment, and LC-MS analysis.