Curcumin was complexed with β-CD using co-precipitation, freeze-drying and solvent evaporation methods. Co-precipitation enabled complex formation, as indicated by the FT-IR and FT-Raman techniques via the shifts in the peaks that were assigned to the aromatic rings of curcumin. In addition, photoacoustic spectroscopy and X-ray diffraction, with the disappearance of the band related to aromatic rings, by Gaussian fitting, and modifications in the spectral lines, respectively, also suggested complex formation. The possible complexation had an efficiency of 74% and increased the solubility of the pure colourant 31-fold. Curcumin-β-CD complex exhibited a sunlight stability 18% higher than the pure colourant. This material was stable to pH variations and storage at -15 and 4°C. With an isothermal heating at 100 and 150°C for 2h, the material exhibited a colour retention of approximately 99%. The application of curcumin-β-CD complex in vanilla ice creams intensified the colour of the products and produced a great sensorial acceptance.

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-A high dosage of albendazole (ABZ) is required for treating systemic helminthe infections because of its low solubility. Aiming at increasing ABZ solubility, complexation with beta-cyclodextrin ( -CD) using aqueous and acetic acid solutions as ABZ solubilizer was studied. In aqueous -CD, complexation increased solubility 53.4 times, giving a complex equilibrium constant of 1266 L mol -1 with a maximum ABZ concentration of 276 µmol L -1 for 16.3 mmol L -1 -CD. For complexation in 1.05 mol L -1 acetic acid, UV absorbance spectra and 1 H-NMR analysis confirmed complex formation. The UV absorbance of ABZ/acid acetic/ -CD solutions was modeled by the formation of two complexes with molar ratios 1:1 and 1:2 ABZ: -CD. When neutralized with NaOH these solutions did not form precipitates only for the ABZ: -CD molar ratios of 1:8 and 1:10, showing that ABZ solubility could be increased 306 times. Results show that high -CD molar ratios hold ABZ in solution by complexation enhanced by the acetate anion.

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