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Updated: Aug 20, 2026

Titration ELISA as a Method to Determine the Dissociation Constant of Receptor Ligand Interaction
Published on: February 15, 2018
A new end-point for ELISA titrations
1Departamento de Personalidad, Facultad de Psicología, Universidad de Barcelona, Barcelona, Spain. jvidal@ub.edu
Abstract:
This report describes a new ELISA procedure based on end-point titrations. This end-point ELISA takes advantage of the change of color intensity that occurs when peroxidase-containing wells of an ELISA plate are revealed with diaminobenzidine-nickel and further intensification with silver: as antibody concentration and, therefore, peroxidase concentration, decreased, the color became stronger in some wells and, afterwards (i.e., at lower antibody and peroxidase concentrations), the color faded toward clear background. It is proposed that the reciprocal of the sample dilution at which the color intensifies can be used as a measure of the sample antibody content. This report verifies the validity and precision of that procedure.
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