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Updated: May 25, 2026

Solubility of Hydrophobic Compounds in Aqueous Solution Using Combinations of Self-assembling Peptide and Amino Acid
Published on: September 20, 2017
The effect of a mild base on curcumin in methanol and ethanol
Yuval Erez1, Itay Presiado, Rinat Gepshtein
1Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, Israel.
Abstract:
Steady-state and time-resolved emission techniques were employed to study the effect of acetate, a mild base, on the luminescence of curcumin in methanol and ethanol. We found that the steady-state emission intensity as well as the average fluorescence decay time are reduced by a factor of 5 when the acetate concentration is raised to about 1.8 M. We attribute this large effect to an excited-state proton transfer (ESPT) from the acidic groups of curcumin to the acetate anion. We analyze the experimental data in terms of an ESPT reaction occurring between a photoacid and a base.
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