Isoparametric analysis of binding and partitioning processes.

An isoparametric method is described for the analysis of titration data pertaining to the binding of a ligand to an acceptor, or to the partition of a molecule between lipid and aqueous compartments. Where spectroscopic titrations are employed, the analysis does not require a priori choice of an association model, nor assumptions concerning a linear relationship between the spectroscopic signal and the amount of bound or partitioned ligand. The method has wide applicability and is illustrated with reference to (a) ligand-acceptor associations monitored by perturbation of the absorption or fluorescence signal of ligand or acceptor, and (b) cross-linking interactions such as those encountered in antigen-antibody precipitin reactions.