CARMEN N. PURDEL*^#, MARINELA FLOREA*, CLAUDIA M. GUȚU*, RUCSANDRA DĂNCIULESCU MIULESCU**, MIHAELA ILIE*, CORINA CRISTINA ARAMĂ*

*Faculty of Pharmacy, ”Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
**”N.C. Paulescu” National Institute of Diabetes, Nutrition and Metabolic Diseases, Bucharest, Romania

Cyclodextrin and their derivatives have the property of forming inclusion complexes with guest molecules having suitable characteristics of polarity and dimension. The paper presents two approaches to explore the possible interaction between fluoxetine and beta-cyclodextrin in aqueous solution: the molecular analysis in vacuo and the experimental characterization of the inclusion complex based on its stability and luminescence characteristics. The molecular modeling predicted the interaction, while fluorescence experiments confirmed it. The spectral characteristics, investigated by fluorescence spectrometry, revealed that the molecular aggregate presents an enhancement of the fluorescence emission at 292 nm, compared with the free ligand or cyclodextrin. The fluorescence intensity of the molecular aggregate depends on the beta-cyclodextrin concentration, but is not affected by the presence of the buffer or its pH value. The molar ratio of the molecular aggregate 1:1 was established using the continuous variation method, while the association constant calculated using Benesi-Hildebrand’s method corresponds to 17.67 mol^–1. Both approaches proved to be useful tools for this type of physical interaction.

Corresponding author’s e-mail: carmenpurdel@gmail.com

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