Interpretation of results from the competitive Biacore procedure for characterizing immunochemical interactions in solution

Rigorous consideration of the consequences of antibody bivalence in the published competitive kinetic procedure for quantifying the solution characteristics of an antigen‐antibody interaction in solution has rendered redundant the practice of substituting the Fab fragment for the antibody to ensure validity of the analysis of results in terms of theory developed for a univalent analyte. Although the quantitative expressions differ for univalent and bivalent analytes, the additional contribution arising from bivalence is likely to be well within the limits of experimental uncertainty in the measured binding constant.