Theoretical analysis of the effects of reversible dimerization in size exclusion chromatography.

Reversible dimer formation in size exclusion chromatography (SEC) can cause peak splitting, merging, tailing, and fronting. Such behavior can be predicted by the association rate and the dissociation rate relative to the convection rate. Slow association and dissociation result in separated monomer and dimer peaks. Fast association and slow dissociation result in one single dimer peak. Slow association and fast dissociation result in one single monomer peak. Intermediate association and dissociation result in a merged, broad peak with either fronting when monomers dominate or tailing when dimers dominate. A diagram based on the two relative rates is generated to predict general peak shape and retention behavior in SEC.