Specific, Reversible Interactions – Protein Binding Studies
The CALYPSO software uses CG-MALS data to calculate the affinity and stoichiometry of specific, reversible complexes formed in solution, such as antibody-antigen interactions and protein dimerization. The software enables quick data fitting to simple models of dimer formation, 1:n stoichiometries, and infinite self-association. Alternatively, the highly versatile analysis tools allow you to choose and design more complex binding schemes, including simultaneous self- and hetero-association, cooperativity, and meta-complex formation.
Nonspecific Interactions –Virial Coefficients
The second virial coefficient (A2) is used to quantify nonspecific attractive and repulsive interactions for proteins, polymers, and colloids. Batch light scattering data collected with the CALYPSO software can be analyzed using a Zimm formalism, Debye formalism, or effective hard sphere approximation. Higher virial coefficients may be determined as well.
Time-Dependent MALS – Association and Dissociation Kinetics
Some protein association or dissociation reactions can take seconds or minutes to reach completion. The CALYPSO software gives you the power to set the time for allowing each composition to come to equilibrium—from a few seconds to several hours. In the example pictured below, different concentrations of a small molecule inhibitor were used to disrupt the dimerization of a protein; the light scattering decrease corresponds to the dissociation of dimers into monomers over time.