Determination of stoichiometric association constants by a non-iterative computational method

Computational methods for the estimation of stoichiometric associationconstants for multiple-ligand binding systems are currentlybased on non-linear least-squares regression analysis. Thesecomputational methods require sophisticated, iterative algorithmsto assure convergence to a solution, as well as initial parameterand error estimates. A simple procedure, called lambda-invariancetesting (LIT), was developed that provides a single-pass (non-iterative)estimation of stoichiometric association constants. The LITmethod was applied to simulated binding data containing Gaussianerror and to real data drawn from the literature. This methodprovided parameter estimates essentially equivalent to thoseobtained by least-squares regression analysis, with no initialparameter or error estimates required. Received on May 26, 1987; accepted on July 27, 1987