Tabriz University of Medical Sciences Pharmaceutical Sciences 1735-403X 31 3 2025 07 03 Solubility of Sildenafil Citrate in Polyethylene Glycol 200+Water Mixtures at 293.2-313.2 K 261 269 10.34172/PS.025.40838 EN Homa Rezaei https://orcid.org/0000-0001-9759-6020 Abolghasem Jouyban https://orcid.org/0000-0002-4670-2783 Journal Article 10.34172/PS.025.40838 2024 09 04 2024 12 03 Background: In the current investigation, the evaluation of model congruence alongside experimental determinations of the solid-liquid phase boundary concerning sildenafil citrate (SICI) within aqueous binary blends of polyethylene glycol 200 has been conducted. Methods: Solubility values were measured using a classical method of Shake-flask at various temperatures. Results: It was observed that the dissolution profile of SICI in the specified binary media demonstrated a positive thermal coefficient. For the determined solubility data, mathematical cosolvency models were employed for the fitting and prediction tasks, showcasing a commendable capability in forecasting the solubility patterns of SICI in the aqueous solutions of polyethylene glycol 200. In addition, apparent thermodynamic quantities pertaining to the dissolution of SICI were computed utilizing both Gibbs and van’t Hoff equations, facilitating an in-depth comprehension of the solubilization phenomena within the studied solvents. Conclusion: The insights gleaned from the rigorous interrogation and validation of the solubility for SICI promise to enhance crystallization methodologies, scale-up production, and pharmaceutical formulation studies.