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CHANGE IN STATE OF WATER OF THEOPHYLLINE HYDRATE BY GRINDING 

作成者 Puttipipatkhachorn, Satit
キーワード等 CRYSTAL WATER, GRINDING, HYDRATES, THEOPHYLLINE
日本十進分類法 (NDC) 499
内容 学位:千大院薬博甲第58号
抄録:The change in state of water of theophylline hydrate by grinding has been studied. Powder X-ray diffraction study revealed that crystalline theophylline monohydrate tended to transform to crystalline anhydrate with increased grinding time. As the grinding time increased, the water content of theophylline hydrate decreased. The dehydration temperature of theophylline hydrate was shifted to a lower temperature by grinding. The ground theophylline hydrate dehydrated in three steps at ca. 58, 44 and 17℃ respectively. The dehydration temperature of ground theophylline hydrate was affected markedly by pressure whereas that of unground theophylline monohydrate was affected slightly by pressure, indicating the change in state of the crystal water. The result of infrared (IR) spectroscopy demonstrated that the hydrogen bonds between crystal water molecules and theophylline molecules were weakened or destroyed to some extent by grinding. It was supposed that crystal water in the ground theophylline hydrate might exist at least in three molecular states of different hydrogen bonding. After storage under 96.5% relative humidity at 30℃, it was suggested that the ruptured hydrogen bonds of water molecules in the ground theophylline hydrate were strengthened. The dehydration process of theophylline monohydrate was further investigated by pressure differential scanning calorimetry (pressure DSC). Pressure DSC curves, measured by using pin-hole aluminum pan, of theophylline monohydrate exhibited two steps of dehydration. Powder X-ray diffraction, IR spectroscopy and low temperature differential scanning calorimetry were used to characterize the pressure DSC endothermic peaks. It was suggested that the endothermic peak at the lower temperature was due to the transition of theophylline monohydrate into theophylline anhydrate and liquid water and the endothermic peak at the higher temperature was assigned to the vaporization of water.…

寄与者 千葉大学大学院薬学研究院
コンテンツの種類 博士論文 Doctoral Thesis
DCMI資源タイプ text
ファイル形式 application/pdf
ハンドルURL http://mitizane.ll.chiba-u.jp/meta-bin/mt-pdetail.cgi?cd=00022537
フルテキストへのリンク http://mitizane.ll.chiba-u.jp/metadb/up/assist1/Y_K-018.pdf
言語 英語


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CRYSTAL WATER
GRINDING
HYDRATES
THEOPHYLLINE