Solubility of sildenafil citrate in the binary mixtures of ethylene glycol and water at different temperatures

The aim of this work is to investigate the solubility behavior of sildenafil citrate (SC) in the binary mixtures of ethylene glycol and water at different temperatures in the range of 293.2–313.2 K. The generated data are correlated with some linear and non-linear cosolvency models including the van't Hoff, the double log-log, the mixture response surface, Yalkowsky, Jouyban-Acree, Jouyban-Acree-van't Hoff, and the modified Wilson models. The mean relative deviations (MRD%) of the back-calculated solubility for each applied models are computed as an accuracy criterion. Density data measured for SC saturated mixtures as another physico-chemical property are also correlated with the Jouyban-Acree model and the results are discussed. Furthermore, apparent thermodynamic properties for SC dissolution process are computed by using van't Hoff and Gibbs equations.