Solubility of carvedilol in ethanol + propylene glycol mixtures at various temperatures

Abstract

Solubilities of carvedilol (CVD) in binary mixtures of (ethanol + propylene glycol (PG)) at 298.2, 303.2, 308.2, and 313.2 K are reported. The modified versions of the van't Hoff and Gibbs equations were used to calculate the thermodynamic properties (enthalpy (?H), entropy (?S), and Gibbs energy (?G) standard changes of solutions) for CVD dissolved in (ethanol (1) + PG (2)) mixtures from the solubility data. The solubility data of CVD in (ethanol (1) + PG (2)) at different temperatures were correlated using different mathematical models, i.e., the Jouyban-Acree model, a combination of the Jouyban-Acree model with the van't Hoff model, and two modified versions of the Jouyban-Acree model. Solubility data of seven drugs in (ethanol (1) + PG (2)) at different temperatures were used to develop a quantitative structure-property relationship model for predicting solubility in solvent mixtures. In addition, enthalpy-entropy compensation using ?H vs ?G and ?H vs T?S which explains the mechanism of cosolvency at different temperatures was discussed. © 2013 American Chemical Society.