Complex Formation between Deoxycholic Acid and Menadione by Grinding and Sealed Heating Methods.

Abstract

Complex formation between deoxycholic acid (DCA) and menadione (MND) by grinding and sealed heating was investigated. The complex between DCA and MND was prepared by coprecipitation and showed a stoichiometry of 2 : 1 (DCA : MND). The IR spectrum of the complex suggested that MND molecules were located in the channel formed by DCA molecules. The 10 min ground mixture of DCA-MND gave the same X-ray diffraction pattern as the DCA-MND coprecipitate. Differential scanning calorimetry (DSC) and IR spectroscopy also demonstrated the identical results between the ground mixture and the complex, confirming the complex formaiton between DCA and MND by grinding. The DSC data suggested that the complex formation was expected during heating process of the DCA-MND physical mixture. The sealed heated samples were prepared and compared with the complex prepared by coprecipitation. After heating in a sealed ampoule at 110°C for 10 min or at 80°C for 24h, samples demonstrated the same X-ray diffraction patterns, DSC curves and IR spectra as the complex. These results indicated that the complex formation took place between DCA and MND by sealed heating as well as by grinding.