Ketoprofen Solubility in Organic Solvents and Aqueous Co-solvent Systems: Interactions and Thermodynamic Parameters of Solvation

Abstract

Ketoprofen (KET) solubility was determined in fifteen pure solvents and aqueous-cosolvent mixtures systems. The results obtained and the parameterized values solvents allowed us to observe the influence of the latter on the solubility of KET. The experimental data obtained indicates that the 𝜋* parameter, which accounts for the polarity/polarizability of the solvent, and the Hildebrand's solubility parameter, which depicts the cohesive forces of the solvent ,has the greatest influence on the solubility of KET. In all the analyzed cosolvent mixtures, the solute was preferentially solvated by the organic cosolvent. This indicates that with a decreasing polarity of the solvent, solvent-solvent interactions decrease, favoring the solute-solvent interactions. For aqueous binary mixtures of ethanol, ethylene glycol and propylene glycol, the apparent enthalpy, entropy and Gibbs free energy changes involved in the solvation process were determined.