Solubility, Thermodynamic Parameters, and Dissolution Properties of 17-α Hydroxyprogesterone in 13 Pure Solvents

Abstract

The static gravimetric method was used to measure the solubility of 17-α hydroxyprogesterone (OHP) in 13 pure solvents ranging from 278.15 to 323.15 K. The results indicate that the experimental solubility of OHP increases with increasing temperature. The experimental solubility data were correlated by the selected van’t Hoff model, λh model, modified Apelblat model, Yaws model, and nonrandom two-liquid (NRTL) model. The fitting results show that the Yaws model can give better correlation results by fitting 13 different pure solvent systems. Based on the NRTL equation, the thermodynamic analysis of solubility data showed that the mixing process was spontaneous. The Hansen solubility parameters (HSPs) and solvent effect were applied to explore these solubility characteristics. Finally, the thermodynamic properties Δsol H°, Δsol S°, Δsol G°, %ξH, and %ξTS were calculated by the van’t Hoff model equation. The results showed that Δsol H°, Δsol S°, and Δsol G° are all positive values, indicating that the dissolution of OHP in the selected solvent is an endothermic reaction with increasing entropy.

Solubility Measurement and Thermodynamic Modeling of Bifendate in 13 Pure Solvents at Temperatures from 293.15 to 333.15 K

“…Currently, the measurement of solubility relies on numerous experiments, resulting in significant consumption of both time and organic solvents. Therefore, many thermodynamic models have been used to predict the solubility of solutes in different solvent systems including the NRTL, − van’t Hoff, − λh, − and Jouyban–Acree − models. Perturbed-chain statistical associating fluid theory (PC-SAFT) has also been successfully applied to describe the phase behavior and calculate the thermodynamic properties of the systems .…”