Solubility of Azilsartan in Methanol, Ethanol, Acetonitrile, n-Propanol, Isopropanol, Tetrahydrofuran, and Binary Solvent Mixtures between 293.15 and 333.15 K

Abstract

A precise determination method of azilsartan solubility between 293.15 and 333.15 K in several ordinary solvents and some of their aqueous mixtures was established by high-performance liquid chromatography. In all tested solvents, its solubility shows exponential growth with the increase in temperature. This trend is especially pronounced in methanol and ethanol. The order of solubility of azilsartan can be expressed as ethanol > tetrahydrofuran > ethanol/water (8/2, v/v) > methanol > methanol/water (8/2, v/v) > n-propanol > isopropanol > ethanol/Water (5/5, v/v) > acetonitrile. The solubility data of azilsartan were well correlated by the λh model. Moreover, the thermodynamic data including the dissolving enthalpy, entropy, and Gibbs free energy of azilsartan in each solvent were calculated which is crucial to its preparation technology study.

Solubility Data, Solubility Parameters and Thermodynamic Behavior of an Antiviral Drug Emtricitabine in Different Pure Solvents: Molecular Understanding of Solubility and Dissolution

“…Computational analysis of experimental solubility value of drugs is important for their practical predictions and validations [ 38 , 46 ]. Hence, the experimental solubility values of ECT in twelve different PS were correlated using three computational models namely the Apelblat, van’t Hoff and Buchowski-Ksiazaczak λh models [ 20 , 32 , 33 , 34 , 35 ].…”

Thermodynamic Analysis of Eplerenone in 13 Pure Solvents at Temperatures from 283.15 to 323.15 K

“…The solubility of a solute is closely related to the thermodynamic properties of solutions. To investigate the thermodynamic behavior of the dissolution process between EP and pure solvents, several thermodynamic parameters such as standard enthalpy of dissolution (Δ sol H° ), standard entropy of dissolution (Δ sol S° ), and standard Gibbs free energy of dissolution (Δ sol G° ) can be analyzed. ,, The standard enthalpy of dissolution (Δ sol H° ) can be calculated according to the van’t Hoff model, as shown in eq ln nobreak0em0.25em⁡ x 1 = − Δ normals normalo normall H ◦ R true( 1 T − 1 T a v true) + b T av = N ∑ i = 1 N 1 T i where x 1 is the molar solubility of EP at temperature T /K and T av is the average harmonic temperature of the experiment. From eq , ln x 1 is linearly related to (1/ T – 1/ T av ), and the slope of the curve is (−Δ sol H° )/ R with an intercept of b , as obtained by graphing with the software.…”

“…To investigate the thermodynamic behavior of the dissolution process between EP and pure solvents, several thermodynamic parameters such as standard enthalpy of dissolution (Δ sol H°), standard entropy of dissolution (Δ sol S°), and standard Gibbs free energy of dissolution (Δ sol G°) can be analyzed. 24,34,35 The standard enthalpy of dissolution (Δ sol H°) can be calculated according to the van't Hoff model, as shown in eq 13…”