While size exclusion chromatography (SEC) handles standard monoclonal antibody aggregation, the physical dynamics shift for complex modalities. At this size regime, SEC's bulk UV-absorbance readout returns one signal per peak for samples such as immunoglobulin M (IgM), while mass photometry's single-molecule counting generates a population histogram. As a result, the two methods produce diverging structural profiles for the exact same sample.
This application note compares parallel data across four antibody samples chosen for the specific analytical questions they raise. The resource examines a clean monomer peak alongside a low-abundance fragment population, an unexpected overlap between retention time and oligomeric state, an off-spec matrix interaction, and a molecule near the column's exclusion limit.
Download the application note to
- Evaluate paired chromatograms and mass histograms from standard monomeric IgG to hexameric IgM
- Pinpoint the exact structural limit where a standard SEC column begins to obscure fragments and oligomers
- Establish a framework for deploying orthogonal single-molecule analysis at scales approaching 1 MDa
