Solubility of Hesperetin in Mixed Solvents

The study of the solubility of important biomolecules such as flavonoids is essential to support the design of several separation processes in the food and pharmaceutical industries. Following our previous studies, new solubility data of hesperetin in the mixed solvents water + acetone, water + ethanol, and water + methanol were measured, at 298.2 K, by the isothermal shake-flask method. The results obtained show three solid-liquid phase diagrams with distinct features. Additionally, the solid crystals obtained from the solubility studies were analyzed by powder X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis indicating that, depending on the mixed solvents composition, two different crystal structures of hesperetin, already described in the literature, can be obtained, corresponding either to the anhydrous or the monohydrate forms.