Correlation of Solid Solubility for Biological Compounds in Supercritical Carbon Dioxide: Comparative Study Using Solution Model and Other Approaches

Solid solubility of biological compounds in supercritical carbon dioxide was calculated using the solution model approach. These solutes include steroids, antioxidants, xanthines and drugs. The regular solution model coupled with the Flory-Huggins equation was employed. The molar volume of the solute in the supercritical phase was optimally fitted. With two parameters in the solution model approach, satisfactory results were obtained which are comparable to those calculated from the equation of state method or semi-empirical equations with more adjustable parameters