Investigating the Dissolution of Ibuprofen and Empagliflozin in Aqueous Deep Eutectic Solvent Systems: Experimental and Thermodynamic Modeling Insights.

Purpose: This study investigated the potential of a deep eutectic solvent (DES) to enhance the dissolution of two poorly water-soluble drugs, ibuprofen (IBU) and empagliflozin (EMPA). The DES was synthesized from tetrabutylphosphonium bromide (TBPB) and diethylene glycol (DEG).

Methods: The apparent solubility of IBU and EMPA was measured in aqueous solutions containing eleven different mass fractions of the DES at temperatures ranging from 20 to 40°C. Dissolution kinetics were monitored over 24 h to differentiate between true equilibrium solubility and supersaturated states. The collected experimental data were then analyzed and correlated using three thermodynamic models: Wilson, NRTL, and UNIQUAC.

Results: The findings indicated that ibuprofen achieved higher dissolution than empagliflozin in the DES-water system. For both drugs, the dissolution process was endothermic, with solubility increasing as both temperature and DES concentration increased. Among the thermodynamic models tested, the UNIQUAC model provided the most accurate correlation with the experimental dissolution data.