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Updated: Feb 7, 2026
An ELISA Based Binding and Competition Method to Rapidly Determine Ligand-receptor Interactions
Published on: March 14, 2016
Single Step Determination of Unlabeled Compound Kinetics Using a Competition Association Binding Method Employing
David A Sykes1, Steven J Charlton2
1School of Life Science, Queen's Medical Centre, University of Nottingham, Nottingham, UK.
Abstract:
The competition association binding method allows the characterization of the kinetics of unlabeled compounds and the calculation of receptor-drug affinity (K d). The K d value is defined as the ratio of the dissociation constant (or k off) of the receptor-bound ligand to its association rate constant (or k on) for a system at equilibrium. Traditionally, competition association binding experiments have been carried out using radiometric detection methods with limited assay throughput. Here we describe a novel method for the determination of unlabeled compound kinetics using the technique of time-resolved fluorescence resonance energy transfer (TR-FRET) performed at physiological temperature and sodium ion concentration. Based on a traditional screening format (10-point curves), up to 28 compounds can be tested on a single 384-well plate by this method.
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