New Thermodynamic Models to Correlate Solubility of Drugs in Supercritical Carbon Dioxide

Experimental measurement and modeling of the solubility of drugs in supercritical carbon dioxide have gained significant attention in the recent past. It is well known that the task of measuring solubility at desired conditions is a mammoth task; hence, modeling is essential. Further solubility is precisely needed in the process of micronizing drug particles with supercritical carbon dioxide (SC-CO2). In order to achieve this, a proper model is required, which will be utilized in predicting the solubility data at desirable experimental conditions. This work focused on the development of new solubility models based on solid-liquid equilibrium criteria. For validation, we have used existing solubility data for several drugs that fall under the antilipemic, NSAID, antibiotic and anti-cancer groups. The proposed models were compared to three existing density models to determine their efficacy, further, the thermodynamic quantities such as total enthalpy of reaction, vaporization, and solvation of the compounds were calculated from existing models. Finally, we have reported a statistical comparison of the models considered in this study.