Apparent thermodynamic analysis and the dissolution behavior of levamisole hydrochloride in three binary solvent mixtures

The solubility of levamisole hydrochloride (LH) in binary {methanol (MT) + ethanol (EA), methanol (MT) + 2-propanol (IPA)} solvent mixtures from 283.15 K to 323.15 K and dimethyl sulfoxide (DMSO) + ethanol (EA) from 293.15 K to 333.15 K were obtained under the pressure of 0.1MPa by using a dynamic method. Moreover, the experimental solubility results of LH in this work were correlated well with five thermodynamic models namely “Yaws model, van’t Hoff model, Universal Quasi-Chemical (UNIQUAC) model, non-random two liquid (NRTL) model and general single (GSM) model”. The minimum RMSD and ARD are 0.0064 and 0.17 respectively and they are both calculated with the GSM model. Besides, the apparent thermodynamic properties of LH in the selected binary solvent mixtures were discussed. Analysis results showed that enthalpy-favored mechanism plays a major role in the dissolution process of LH.