NaClナノ粒子の凍結乾燥ダイナミクスをTHzスペクトル法で捉える
Katsuhiro Ajito1, Yuko Ueno2, Jae-Young Kim1
1NTT Device Technology Laboratories , NTT Corporation , Atsugi 243-0198 , Japan.
Journal of the American Chemical Society
|October 24, 2018
まとめ
凍結乾燥 過程 で 研究 者 たち は 細胞 単位 の 大きさ の 塩化 ナトリウム (NaCl) の 粒子 を 発見 し まし た. この発見は 極細な製薬粉末を作るための冷凍乾燥技術の開発に 新たな可能性を秘めています
科学分野:
- 物理化学
- 材料科学
- クリスタルグラフィー
背景:
- 塩化ナトリウム (NaCl) 溶液は低温でNaCl水素 (NaCl·2H2O) を形成し,食品および医薬品における冷凍乾燥試験のモデルとして使用されている.
- 凍結中のNaCl結晶化の理解は,凍結乾燥プロセスを最適化するために重要です.
研究 の 目的:
- 水溶液の凍結中のNaCl結晶化の初期段階を調査する.
- 先進的なスペクトロスコーピテクニックを用いてNaCl水素形成の前駆物質を特定する.
主な方法:
- テラヘルツ (THz) スペクトロスコピーは,NaCl溶液の凍結中に粒子を検出および分析するために使用されました.
- 分析は単位細胞の大きさの粒子とそのスペクトルシグネチャを特定することに焦点を当てました.
主要な成果:
- NaCl溶液の凍結過程で,以前は相図で記録されていない,単細胞サイズのNaCl粒子が検出されました.
- NaCl·2H2O形成の前駆体として2種類の転移性単細胞サイズのNaCl粒子が特定されました.
- これらの前体粒子は テラヘルツスペクトルにおいて 明確な吸収ピークを示した.
結論:
- 単細胞サイズのNaCl粒子の存在は,凍結中のNaCl結晶化の複雑さを強調しています.
- この発見により 凍結乾燥の過程について 新たな洞察が得られました
- ナノメートルの大きさの粒子を製造する新しい冷凍乾燥技術,例えば溶解性が向上した超微細な製薬粉末の開発への道を開きます.
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