Structure-property relationships on recrystallized ß-cyclodextrin solvates: A focus on X-ray diffractometry, FTIR and thermal analyses.

The goal of the study was to evaluate the influence of the solvent properties on the crystal characteristics of ß-cyclodextrin (ß-CD) recrystallized from alcohol-water solvent mixtures, with possible applications for the preparation, purifying and complexation of ß-CD. For the first time, structure-property relationships (QSPRs) between the hydrophobicity of alcohols or dielectric constant of solvents used for recrystallization of ß-CD and its properties (such as crystallinity index, CI) have been obtained. Recrystallized ß-CD from water and C1-C4 alcohol-water solutions provide ß-CD with higher CI values of 99.4(±5.9)% for ethanol-water (1:4, v/v) as recrystallizing system. This property has a parabolic variation with the logP (octanol/water partition coefficient) of the alcohol (r2 = 0.998). Solvent parameters also influence the ß-CD crystal characteristics, as was demonstrated by X-ray diffractometry refinement, infrared spectroscopy and thermal analyses.

Moisture evaluation of ß-cyclodextrin/fish oils complexes by thermal analyses: A data review on common barbel (Barbus barbus L.), Pontic shad (Alosa immaculata Bennett), European wels catfish (Silurus glanis L.), and common bleak (Alburnus alburnus L.) living in Danube river.

The moisture content of ß-cyclodextrin/Danube fish oils complexes (common barbel, Pontic shad, European wels catfish, common bleak) was evaluated by thermal methods. Saturated and monounsaturated fatty acids were the most concentrated in fish oils (25.3-30.8% and 36.1-45.0%). ω-3 And ω-6 fatty acids were identified in low concentrations of 2.8-12.1% and 4.1-7.1%. The moisture content was significantly lowered after ß-CD complexation, as revealed by thermogravimetric (TG) analysis (13.3% for ß-CD, 2.5-6.5% for complexes). These results are consistent with the differential scanning calorimetry (DSC) data for the peaks corresponding to dissociation of water (calorimetric effect of 536Jg-1 for ß-cyclodextrin and 304-422.5Jg-1 for complexes). Furthermore, both TG and DSC results support the formation of inclusion complexes. This is the first study on the nanoencapsulation of Danube fish oils in ß-cyclodextrin.