Solubility of Bifonazole in Four Binary Solvent Mixtures: Experimental Measurement and Thermodynamic Modeling

Abstract

Methanol (n-propanol, isopropanol, and propylene glycol) and water were mixed in different proportions to form four mixed solvents, which were applied to dissolve bifonazole. The mole fraction of bifonazole was determined by the isothermal dissolution equilibrium technique within T = 278.15–318.15 K and P = 101.1 kPa under the condition that the dissolution system reached equilibrium. The increase in the ratio of organic solvent to water in the mixed solvents and temperature promoted the increase in the solubility of bifonazole. The solvent formed by mixing methanol and water in different proportions was most beneficial for the dissolution of bifonazole in all solution systems at the same percentage of organic solvent and the same temperature. Moreover, the calculated results of the Jouyban–Acree model, the van’t Hoff–Jouyban–Acree model and the modified Apelblat–Jouyban–Acree model are in good agreement with the solubility data of the experimentally measured bifonazole. The mole fraction calculated by the model is not completely consistent with the experimental result, and the maximum average relative deviation between them is 2.76%. The determination of the solubility data of the drug in the mixed solvent is of great value for the improvement of the physical and chemical information of the drug and the analysis of the thermodynamic properties.