Evaluation of an index based on van't Hoff equation to predict PEG-drug eutectic composition

Five poorly soluble drugs namely hydrochlorothiazide, menadione, propylthiouracil, quinine sulfate and sulfamerazine were used to evaluate the ability of an index (I _c) based on the van't Hoff equation to predict the eutectic composition at a higher heating rate than previously published. The term I _c is a dimensionless index which has been defined in the literature and is used to predict eutectic composition. This current work uses this study to determine if the correlation holds true at the higher heating rate of 10°C min^-1. The maximum deviation was observed for quinine sulfate, for which the predicted eutectic composition was 10% lower than what was observed with the DSC. It can be concluded that the Index developed here has a good correlation with the experimentally determined eutectic composition. This revised version was published online in July 2006 with corrections to the Cover Date.