Solubility and thermodynamic study of deferiprone in propylene glycol and ethanol mixture

Abstract

Introduction:Solubility is one of the most important physico-chemical properties of pharmaceutical substances. Solubility data provide practical information for the preparation of pharmaceutical formulations, the development of pharmaceutical analyses, recrystalization in the purification process, and solid phase properties and extraction.Aims:Our goal in this research is to investigate the thermodynamic solubility of deferiprone in the mixture of propylene glycol and ethanol solvents and to predict the solubility data with cosolvency models.Method:In this research, the shake flask method was used to measure the solubility of deferiprone in the solvent system of propylene glycol and ethanol. In this way, an excess amount of the drug was poured into the container containing cosolvent + solvent, after reaching the equilibrium of the solution at the set temperature, the supernatant solution was separated from the remaining solid material by centrifugation and after proper dilution, the absorbance was read at a wavelength of 273.5 nm with a UV-Vis spectrophotometer. Then, by referring to the calibration curve that we previously ensured its accuracy, the concentration of the samples was obtained. Results:Based on the data obtained from the experiments, we find that the solubility of deferiprone increases with the increase of the mass fraction of propylene glycol and the temperature, so that the highest solubility obtained for deferiprone in the solvent system corresponds to the mass fraction of 0.85 of propylene glycol at a temperature of 313.2 degrees Kelvin, and then increasing the amount of propylene glycol, the solubility decreases.Conclusion:The present study investigates the solubility of deferiprone in the binary mixtures of propylene glycol and ethanol at five different temperatures. the solubility of deferiprone is dependent on the temperature and the composition of the solvents, and the experimental data obtained are analyzed with different cosolvency models. and the error of the studied models is less than 3%.