CHAMELEONIC EFFECT AND SOME MODELS FOR PREDICTING DRUG SOLUBILITY IN SOLVENT MIXTURES

A new model derived from an excess free energy approach which expresse s drug solubility in solvent mixtures showing multiple solubility peak s, the chameleonic effect, with respect to the concentrations of solve nts in a mixture is proposed. Accuracy and predictability of the model are compared with those of a previous model which expresses drug solu bility based on Hildebrand, acidic and basic solubility parameters. Th e results indicate that the new model is more accurate than the previo us model and average percent mean errors are 5.32 and 13.66, respectiv ely.