Solubility determination and correlation for azithromycin monohydrate and dihydrate in solvent mixtures

The solubility of azithromycin monohydrate in binary solvent mixtures (ethanol + water and propanol + water) was studied by a static method with a temperature range from 283.151< to 323.15 K under atmospheric pressure. Besides, azithromycin dihydrate in acetone + water binary solvent mixtures was reported with temperature ranging from 283.15 K to 323.15 K. Results showed that the solubility of azithromycin monohydrate and dihydrate in binary solvent mixtures all increased with temperature and the content of organic solvents. The solubility data in binary solvent mixtures were correlated by van't Hoff-Jouyban-Acree model, Apelblat-JouybanAcree model, Ma model and Sun model, and all models could be used to correlate the solubility of azithromycin monohydrate and dihydrate in the solvent mixtures. All the result mentioned in this study could help purify azithromycin monohydrate and dihydrate. (C) 2019 Published by Elsevier B.V.