Solubility of three basic drugs in propylene glycol + water mixtures in the presence of β-cyclodextrin

Cosolvency and complex formation are the important methods to increase the solubility of drugs. These methods can be used to change solubility simultaneously. In this study, solubilities of three basic drugs, i.e. atenolol, diazepam and lamotrigine, were studied in binary mixtures of propylene glycol + water in the presence of cyclodextrin (CD) and atenolol in this solvent mixture in the absence of CD using saturating shake flask method. The generated solubility data was fitted to the Jouyban-Acree model and the solubility profile of each drug was compared with solubility data in the absence of CD that the solubility data of diazepam and lamotrigine taken from the literature.