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Updated: Mar 15, 2026

A Rapid and Quantitative Fluorimetric Method for Protein-Targeting Small Molecule Drug Screening
Published on: October 16, 2015
Evaluation of pendimethalin binding to human serum albumin: Insights from spectroscopic and molecular modeling
Wei Qi Lee1, Ida Syazwani M Affandi1, Shevin R Feroz1
1Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Abstract:
Interaction of pendimethalin (PM) herbicide with the major transporter in human circulation, human serum albumin (HSA), was studied using fluorescence, circular dichroism (CD), and molecular modeling methods. The attenuation of the fluorescence intensity of HSA in the presence of PM revealed formation of the PM-HSA complex. Analysis of the fluorescence quenching data showed moderately strong binding affinity between PM and HSA. Both hydrophobic interactions and hydrogen bonding were suggested to stabilize the PM-HSA complex, based on thermodynamic data. Binding of PM to HSA induced perturbation in the microenvironment around the aromatic fluorophores as well as secondary and tertiary structural changes in the protein. Complexation of PM with HSA led to an increase in its thermal stability. Both site marker displacement and molecular modeling results suggested site I, located in subdomain IIA as the preferred binding site of PM on HSA.
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