Study of \u3b2-blockers/\u3b2-cyclodextrins inclusion complex by NMR, DSC, X-ray and SEM investigation

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Study of flavonoids/beta-cyclodextrins inclusion complexes by NMR, FT-IR, DSC, X-ray investigation

Flavonoids are natural substances with a lot of biological activities, including the antioxidant one. Their use in pharmaceutical field is, however, limited by their aqueous insolubility. As the formation of the inclusion complexes can improve their solubility in water, the flavonoids hesperetin, hesperidin, naringenin and naringin have been complexed with beta-cyclodextrin (beta-CD) by the coprecipitation method and studied in solution and in solid state by NMR, FT-IR, differential scanning calorimetry and X-ray techniques, The effects of complexation on the chemical shifts of the internal and external protons of beta-CD in the presence of each flavonoid were observed. (C) 2002 Elsevier Science B.V. All rights reserved

Structure of beta-blockers/beta cyclodextrin inclusion complex by NMR, X-Ray and DSC investigation

The inclusion complexes between two beta-blockers, atenolol and celiprolol, and the beta-cyclodextrin has been investigated in solution and in the solid state using X-Ray, DSC and NMR

Effects of alpha- and beta-cyclodextrin complexation on the physico-chemical properties and antioxidant activity of some 3-hydroxyflavones.

Inclusion complexes of some flavonols (3-hydroxyflavone, morin and quercetin) have been obtained with alpha- and beta-cyclodextrins, by the co-evaporation method. Different analytical techniques (DSC, XRPD, FT-IR, H-1-NMR, UV-Vis) have been employed for a throughout investigation of the structural characteristics of such supramolecular aggregates, which exhibited distinct spectroscopic features and properties from both guest and host molecules. The stoichiometric ratios and stability constants describing the extent of formation of the complexes have been determined by phase-solubility studies; in all cases type-A(L) diagrams have been obtained (soluble 1: 1 complexes). The effect of molecular encapsulation on the flavonols antioxidant activity has been afterwards evaluated, by means of different biological assays (Bathophenanthroline test; Comet assay; Lipid peroxidation). Complexation with cyclodextrins further improved the antioxidant activity, increasing drugs solubility in the biological moiety