Harnessing Solubility Parameter-based Approaches to Predict Aripiprazole’s Solubility in Solvent Mixtures

Solutions of drugs may behave as ideal solutions, real solutions, or irregular solutions. It is necessary to understand the behaviour of these solutions before attempting to handle them. Various theories/models are reported in the literature to explain their behaviour. The importance of models in predicting the solubility of aripiprazole is demonstrated using its solubility in dioxane-water blends. The method utilizes theoretical and semiempirical approaches to predict solubility. The experimental solubility data for aripiprazole are validated using both ideal and nonideal solutions, focusing on the Scatchard-Hildebrand equation for regular solutions. Furthermore, the Extended Hildebrand Solubility approach is employed to identify the most suitable equation that yields calculated solubility data in agreement with experimental results. Interestingly, a method that directly correlates the solubility parameter of solvent combinations with the logarithm of the mole fraction solubility produces findings comparable to those obtained with the Extended Hildebrand Solubility approach. The results imply that aripiprazole solutions behave as irregular solutions. The solubility profile of aripiprazole may be precisely determined using a quartic equation developed based on regression of activity coefficient versus solubility parameter of the solvent blends. This method saves time and money compared to experimental methods.