https://www.hal.inserm.fr/inserm-00709735/document

Nanoemulsion formulation of fisetin improves bioavailability and antitumour activity in mice.

Liposomal encapsulation of the natural flavonoid fisetin improves bioavailability and antitumor efficacy.

Inclusion of chrysin in β-cyclodextrin nanocavity and its effect on antioxidant potential of chrysin: A spectroscopic and molecular modeling approach

Development of a liposomal formulation of the natural flavonoid fisetin.

Comprehensive Supramolecular Chemistry. 11 Volumes. Editor-in-chief Jean-Marie Lehn (Université Louis Pasteur, France). Edited by Jerry L. Atwood (University of Missouri), J. Eric Davies (University of Lancaster, U.K.), David D. Macnicol (University of Glasgow), and Fritz Vogtle (Friedrich-Willhelms-Universität, Germany). Pergamon: Oxford. 1996. 6672 pp. $4320. ISBN 0-08-040610-6 (set).

In this work, the interaction between fisetin (3,3',4',7-tetrahydroxyflavone) (Fis) and cyclodextrins (CDs) (alpha and beta) was studied through UV-vis absorption, steady-state fluorescence, induced circular dichroism, and (1)H NMR experiments with dependence on temperature and pH. Some experimental data were compared with quantum-mechanics studies based on the SAM1 (AMPAC) semiempirical model, as well as with the B3LYP and MPW1PW91 functional models from density functional theory using the 6-311G and 3-21G basis sets. The spectroscopic measurements show that Fis does not form stable complexes with alpha-CD. On the other hand, at pH 4.0 and 6.5, the complex Fis-beta-CD is formed in a Fis:beta-CD 1:1 stoichiometry and an equilibrium constant (K) of 900 +/- 100 M(-1). In basic medium (pH 11.5), K decreases to 240 +/- 90 M(-1) because Fis deprotonation leads to its better solubilization in water. Molecular modeling points out that Fis is not totally inserted into the inner cavity of beta-CD. The formation of the inclusion complex renders an environment that enhances intramolecular excited state proton transfer. The inclusion complex is formed preferentially via entry of the Fis phenyl group into beta-CD.

Study of the complexation of fisetin with cyclodextrins

This paper aimed to study the mode of inclusion for 7-hydroxyflavone (7HF) in β-cyclodextrin (β-CD) complex in basic (pH 12) and acid (pH 4.5) media. The thermodynamic parameters of the complexation of 7HF with β-CD were evaluated by means of steady-state fluorescence and solubility measurements at several temperatures. The 7HF–β-CD inclusion complex was spontaneously formed at 1:1 stoichiometry in both basic and acid media. The high number of hydrogen bonds formed between the host and the guest molecules favored complexation in the basic medium, with a ground-state equilibrium constant (K) of 990 ± 130 mol −1 L, at 25 o C. The quantum-mechanics calculations showed that complexation of 7HF (neutral or anionic form) with β-CD occurred mainly via the phenyl group of the flavonoid. This result agreed with the induced circular dichroism signal of 7HF complexed with β-CD.

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Mariana R. Guzzo

Papers

Study of the complexation of fisetin with cyclodextrins

Study of the Mode of Inclusion for 7-Hydroxyflavone in β-Cyclodextrin Complexes