Overview
Antibody-drug conjugates (ADCs) combine the target specificity of monoclonal antibodies with the cytotoxic potency of small-molecule payloads. A key challenge encountered in the development of these therapeutics is that the conjugation chemistry can perturb antibody structure, stability, and target-binding function in ways that are difficult to characterize. Here we present an integrative biophysical characterization workflow that compares an unconjugated antibody to its corresponding ADC using three complementary methods: circular dichroism spectroscopy (Chirascan) to assess secondary and tertiary structural integrity, surface plasmon resonance (Alto) to quantify antigen-binding affinity and kinetics, and intrinsic
DSF (SUPR-DSF) to evaluate stability. By layering conformational, interfacial, and thermal stability data, we identify which biophysical attributes shift upon conjugation and link these changes to functional consequences for target engagement. This multi-technique approach demonstrates how combining orthogonal biophysical methods provides a complete picture of ADC critical quality attributes, supporting more informed decision-making in ADC development.
