Temperature and pH effects on the formation of cyclodextrin-fluorouracil and cyclodextrin-uracil complexes.

Abstract

This study analyses the effects of pH and temperature on cyclodextrin-fluorouracil and cyclodextrin-uracil complexes. Fluorouracil is a chemotherapy drug given in high dosages leading to severe adverse effects. To reduce the severity of these effects, the drug would need to be more water soluble increasing the efficacy of the drug. To increase the water solubility, a host molecule cyclodextrin is used to form an inclusion complex with the drug. The thermodynamic properties and chemical equilibria were determined of different pH and temperature environments to gain a better understanding of this complex formation. It was found that the reaction between the host-guest molecules is a spontaneous process, endothermic, and entropy- driven. As the temperature increases, the number of host-guest molecules increase.