Solubility determination, various solubility parameters and solution thermodynamics of sunitinib malate in some cosolvents, water and various (Transcutol plus water) mixtures

Temperature-dependent solubility data and other physicochemical parameters of sunitinib malate (SM) are scarce in literature. Therefore, in this research, the solubility, various solubility parameters and dissolution thermodynamic properties of SM in six cosolvents {i.e., ethanol, isopropanol (IPA), ethylene glycol (EG), propylene glycol (PG), polyethylene glycol-400 (PEG-400) and Transcutol-HP (THP)}, water and various THP + water mixtures at T = 298.2 K to 318.2 K and p = 0.1 MPa were determined. The experimental solubilities of SM were validated using five different computational models such as van't Hoff, Apelblat, Yalkowsly-Roseman, Jouyban-Acree and van't Hoff-Jouyban-Acreemodels. All the studied models performed good correlation and validation. Various solubility parameters of SM, cosolvents, water and different THP + water mixtures were estimated to select the best solvent for SM solubility/miscibility. The mole fraction solubilities of SM were obtained maximumin pure THP (1.87 x 10(-2)) followed by PEG-400, IPA, ethanol, PG, EG and water (1.05 x 10(-5)) at T = 318.2 K. The similar trends of solubility were also found at T = 298.2, 303.2, 308.2 and 313.2 K. Most of the solubility parameters of SM were found to very close with pure THP. Apparent thermodynamic analysis suggested an endothermic and entropy-driven dissolution of SM in six different cosolvents, water and all THP + water mixtures. The maximum interactions at molecular level were found in SM-THP in comparison with other SM-cosolvents and SM-water combinations. Based on these results, THP has been chosen as the best cosolvent for solubility/miscibility of SM. (C) 2020 Elsevier B.V. All rights reserved.y