Correlation and prediction of drug molecule solubility with the NRTL-SAC model

The recently proposed Nonrandom Two-Liquid Segment Activity Coefficient model (NRTL-SAC) of Chen and Song (2004) provides a simple and thermodynamically consistent framework to correlate and predict drug solubility in pure solvents and mixed solvents, based on a small initial set of measured solubility data. Used within a process simulator, or through an Excel spreadsheet, the model forms the scientific foundation of an effective solubility modeling tool in support of early stage crystallization process development. The methodology is also applicable to other unit operations where phase equilibrium calculations factor prominently in process design and development.