| To improve the solubility of a weakly water-soluble drug of naproxen, a deep eutectic solvent (DES) based on choline chloride with propylene glycol as a green solvent is applied from 0.0 up to 1.0 mass fractions of DES at T = (293.2 to 313.2) K. Five cosolvency models including Jouyban-Acree, Jouyban-Acree-van't Hoff, van't Hoff, the mixture response surface and the Buchowski–Ksiazczak models were used to correlate the generated solubility data. The mean relative deviations (MRD %) is applied for the accuracy investigation of the models. Moreover, the respective apparent thermodynamic quantities of the dissolution and solvation processes, namely Gibbs energy, enthalpy, and entropy, are also calculated based on the van’t Hoff and Gibbs equations. |