Dimensionless Empirical Model to Correlate Pharmaceutical Compound Solubility in Supercritical Carbon Dioxide

The accurate experimental determination of pharmaceutical compound solubilities at various temperature and pressure ranges in supercritical carbon dioxide (ScCO2) is a challenging and time-consuming task. Therefore, prediction or correlations of solute solubilities are essential for implementation of ScCO2 technologies to pharmaceutical industries. Solubilities of 41 pharmaceutical compounds in ScCO2 are correlated by an empirical model, which is developed based on the degree of freedom analysis. Its correlating ability is compared with existing solubility models elaborated by other authors and evaluated in terms of global mean absolute relative deviation, sum of squares due to error, root mean square deviation, R-2, and Adj. R-2. The proposed model is found to correlate better than existing models.