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Updated: May 4, 2026

A Rapid and Quantitative Fluorimetric Method for Protein-Targeting Small Molecule Drug Screening
Published on: October 16, 2015
Investigation of the interaction between five alkaloids and human hemoglobin by fluorescence spectroscopy and
Wu He1, Huanjing Dou1, Zhigang Li1
1College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, PR China.
Abstract:
This work studied the interaction of human hemoglobin (HHb) with aminophylline, acefylline, caffeine, theophylline and diprophylline systematically by UV-vis absorption spectroscopy and fluorescence spectroscopy in combination with molecular modeling. Five alkaloids caused the fluorescence quenching of HHb by the formation of alkaloids-HHb complex. The binding constants and thermodynamic parameters were obtained. The hydrophobic and electrostatic interactions were the predominant intermolecular forces to stabilize these complexes. Results of thermodynamic analysis and molecular modeling showed that aminophylline was the strongest quencher and diprophylline was the weakest quencher.
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