固体ダイナミック核極化 9.4 と 18.8 T で 100 K から 室温
Moreno Lelli1, Sachin R Chaudhari1, David Gajan1
1Institut de Sciences Analytiques, Centre de RMN à Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) , 69100 Villeurbanne, France.
Journal of the American Chemical Society
|November 12, 2015
まとめ
ダイナミックな核極化 (DNP) を用いた高感度核磁共振 (NMR) 実験は,今より高い温度で可能です. 研究者は,特定の溶媒を用いて240Kで (1) H DNPの有意な増強を達成し,新たな応用が可能になった.
科学分野:
- 固体核磁共振 (NMR) スペクトロシー
- 動的核極化 (DNP) テクニック
- 材料科学と物理化学
背景:
- ダイナミック・ニュークレア・ポラライゼーション (DNP) は,NMR信号の感受性を大幅に高めます.
- 現在のDNP方法は通常,低温 (≤100K) に制限されています.
- 高温のDNPは,より広範なアプリケーション,特に生物学的および材料科学において不可欠です.
研究 の 目的:
- 高温で効率的なダイナミックな核極化 (DNP) を達成する可能性を調査する.
- 高温DNPの特定の溶媒とバイラジカルの使用を調査する.
- 固体製薬化合物の分子動態をモニタリングするために高温DNPを適用する.
主な方法:
- オルトテルフェニル (OTP) で溶解したビラジカルTEKPolを溶媒システムとして使用した.
- 100〜300Kの温度範囲で (1) Hの交差効果DNP実験を行った.
- 9.4と18.8テスラの磁場で実験を行いました
- アンブロクソールとイブプロフェンの固体における分子動力学的移行を研究するためにDNPを適用した.
主要な成果:
- 240 K で 80 を超える (1) H クロス効果の DNP 強化を達成した.
- OTPのガラス化温度 (Tg = 243 K) を上回るDNP強化の比較的遅い低下が観察されました.
- (1) 環境温度で1520のH DNP増強が得られた.
- アムブロクソールとイブプロフェンの分子ダイナミックトランジションは,開発されたDNP方法を使用して,成功裏にモニタリングされました.
結論:
- 効率的な高温DNPは,オーソテルフェニル (OTP) などの適切な溶媒システムを選択することによって達成できます.
- 開発された方法は,従来の限界を大幅に上回る温度でDNP強化のNMR研究を可能にします.
- この技術は,薬学的に重要な固体物質の分子ダイナミクスを環境に近い条件で調査するための貴重なツールを提供します.
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