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Updated: Jul 5, 2026
Bio-layer Interferometry for Measuring Kinetics of Protein-protein Interactions and Allosteric Ligand Effects
Published on: February 18, 2014
Ligand characterization using microphysiometry
1Molecular Devices Corporation, Sunnyvale, California, USA.
Abstract:
This unit describes the use of a Cytosensor microphysiometer for functional characterization of an agonist and antagonist to a G protein-coupled receptor, the muscarinic M1 receptor. Concentration-response profiles are used to calculate values for the EC50 of the response of cells to the agonist and the pA2 value for the antagonist. Support protocols describe optimization of two aspects of this procedure: the duration of ligand exposure at a given concentration and the length of recovery time between the administration of two different concentrations of ligand to minimize the impact of desensitization. The Cytosensor microphysiometer allows the measurement of receptor activation in both adherent cells, such as the M1WT3 cells used here or in suspension cultures.
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