Related Experiment Video
Updated: Jan 30, 2026

Real-time Analyses of Retinol Transport by the Membrane Receptor of Plasma Retinol Binding Protein
Published on: January 28, 2013
Exploring ligand-protein interaction: A laboratory exercise on herbicide binding to plasma transport protein
Amira Adlin Roslan1, Saad Tayyab1
1Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
Abstract:
A laboratory exercise on the interaction between the herbicide pendimethalin (PM) and goat serum albumin (GSA), a carrier protein present in mammalian blood circulation, is described. Fluorescence spectroscopy was used to study the binding reaction between PM and GSA. Titration of a constant amount of the protein (GSA) with increasing ligand (PM) concentrations produced a consecutive decrease in the protein's fluorescence. Treatment of the fluorescence quenching data according to the Stern-Volmer equation yielded the values of the Stern-Volmer constant (Ksv ) and bimolecular quenching rate constant (kq ), whereas values of the binding constant (Ka ) and number of binding sites (n) were obtained from the double logarithmic plot. This experiment provides an exciting opportunity for undergraduate students to independently perform ligand binding studies with a protein, in addition to providing the means for the determination of their binding parameters. © 2019 International Union of Biochemistry and Molecular Biology, 47(2): 156-160, 2019.
Related Concept Videos
Ligand Binding Sites
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Ligand Binding and Linkage
Drug Distribution: Plasma Protein Binding
Factors Affecting Protein-Drug Binding: Drug Interactions
Displacement interactions can have varying outcomes, ranging from toxicity to virtually...
Protein-protein Interfaces
Conservation of Protein Domains Over Different Proteins
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to...

