Modeling, solubility, and thermodynamic aspects of sodium phenytoin in propylene glycol-water mixtures

The solubility of sodium phenytoin in binary mixtures of propylene glycol and water at 298.2, 303.2, 308.2, and 313.2 K was measured. The effect of solvent composition on the thermodynamic properties of the dissolution process, including enthalpy, entropy, and Gibbs energy were studied based on van't Hoff analysis and the Gibbs equation. Experimental solubility was determined using the shake-flask method and the resulting data were correlated with the Jouyban-Acree model and with the Jouyban-Acree model in combination with the van't Hoff equation.