Session: Physical Chemistry Poster:

Flavonoids are natural products often found in natural sources and have biological properties of great interest and rutin has a structure with a flavan nucleus, in addition to a large glycid group, totaling 10 hydroxyl groups, which suggests a high solubility in water. The solubility of drugs is a fundamental property in their action in the human body, affecting their bioavailability at the site of action. The determination of free energy of solvation (ΔG_solv) can provide a prediction of the tendency of a solute to be dissolved by a solvent and molecular modeling is a powerful tool for estimating this property, in addition to providing structural data for analyzing the interaction between solute and solvent molecules.
Figure 1a shows the ΔG_solv for eight solvents and the negative of solubility of rutin in these liquids. It can be seen that, for liquids capable of interacting with only hydrogen bonds (such as water), the solubility of rutin is very low and that the lowest ΔG_solvvalues occur for alcohols with low molar mass. In addition, for ethanol-water mixtures with x_ethanol=0.4, the ΔG_solv is more negative (Figure 1b). In this system, the structural analysis reveals that water and ethanol are concentrated in different regions of the glycidic fraction, which suggests that the solubilization of rutin depends on a solvent that covers groups that participate in H-bonds and also CH_n groups, participants in dispersion forces. These results point to the advantage of choosing solvent blends, important in the extraction process from natural sources.

Andrew Paluch

Appearances