ピロキシカムのメカノクロミズムは,分光学方法と固体相変化によって探査された分子間陽子移転に伴います
Agam R Sheth1, Joseph W Lubach, Eric J Munson
1Department of Pharmaceutics, College of Pharmacy, University of Minnesota, Weaver-Densford Hall, 308 Harvard Street SE, Minneapolis, MN 55455-0343, USA.
Journal of the American Chemical Society
|May 5, 2005
まとめ
機械的なストレスは,結晶のピロキシカムを,電荷のある分子に起因する黄色い無形ピロキシカムに変換します. このメカノクロミズムは,固体NMRで定量化され,機械的ストレス誘発障害の際に陽子の移転を強調しています.
科学分野:
- 固体化学 固体化学
- マテリアルサイエンス 材料科学
- 物理化学 物理化学とは
背景:
- 非ステロイド性抗炎症薬であるピロキシカムは,異なる固体形態を示しています.
- ストレス下での構造的変化を理解することは,薬剤の安定性および配方にとって極めて重要です.
- 以前の研究では,黄色いピロキシカムの形態にズウィテリオン分子が含まれていることが示されました.
研究 の 目的:
- 機械的ストレス下における結晶型ピロキシカムの構造的および固体状態の変化を調査する.
- 機械的ストレスによって引き起こされる色変化の背後にあるメカニズムを解明する.
- アモルフォース・フェーズに存在する分子種を定量化するために.
主な方法:
- 機械的ストレスを誘発するために冷凍研磨.
- 構造分析のための粉末X線微分測定法 (PXRD).
- 色の変化のための固体UV-Visスペクトロスコピー.
- 分子定量化のための可変温度固体 (13)C核磁共鳴 (NMR) スペクトロスコーピー.
- 固体分散反射赤外線フーリエ変換スペクトロスコーピー (DRIFTS) 機能群分析.
主要な成果:
- 機械的ストレスは,無色結晶のピロキシカム無水素を黄色い無形ピロキシカムに変形させた.
- 無形ピロキシカムの黄色い色は,電荷のあるピロキシカム分子と関連しています.
- 温度変数固体 (13) C NMRは,無形相には約8%の電荷のピロキシカム分子が含まれていることを明らかにしました.
- アモルフォスピロキシカムは,無色結晶相に再結晶する傾向を示した.
結論:
- 機械的ストレスはピロキシカムのメカノクロミズムを誘発し,陽子の移転と無色から黄色に色の変化を伴う.
- 固体NMRは,標準化されていない無形薬物段階における中性および有電荷種を定量化するための強力なツールです.
- この研究は,ピロキシカムの機械的ストレス,固体状態障害,陽子転送,および色変化の間の直接的な関連性を示しています.
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