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Updated: Jun 3, 2026
07:49
Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Interaction between bisphenol A and tannic acid: spectroscopic titration approach
Anselm Omoike1, Benjamin Brandt
1Department of Chemistry and Biochemistry, University of Michigan-Flint, Flint, MI 48502-1950, United States. ansomo@umflint.edu
Summary
Tannic acid (TA) effectively quenches bisphenol A (BPA) fluorescence through static quenching, forming a spontaneous complex. Hydrogen and van der Waals forces drive this interaction, revealing insights into endocrine disruptor binding.
Area of Science:
- Environmental Chemistry
- Biochemistry
- Analytical Chemistry
Background:
- Bisphenol A (BPA) is a common endocrine disruptor with potential health implications.
- Understanding the molecular interactions of BPA with other compounds is crucial for assessing its environmental fate and biological effects.
Purpose of the Study:
- To investigate the binding interaction between tannic acid (TA) and bisphenol A (BPA).
- To elucidate the thermodynamic parameters and driving forces governing the formation of the TA-BPA complex.
Main Methods:
- Absorption and fluorescence titration techniques were employed to study the TA-BPA interaction.
- Binding constants and thermodynamic parameters were determined at various temperatures (294–303 K).
Main Results:
- Tannic acid (TA) caused significant quenching of bisphenol A (BPA) intrinsic fluorescence, indicating complex formation.
- The quenching mechanism was identified as static quenching.
- Thermodynamic data showed the TA-BPA complex formation to be exothermic, spontaneous, and entropic-driven.
Conclusions:
- The formation of the nonfluorescent TA-BPA complex is primarily driven by hydrogen and van der Waals interactions.
- This study provides valuable thermodynamic insights into the binding of BPA with tannic acid.
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