リレーされたパラマグネティック・リラクゼーション・エンハンスメントによって決定される材料のナノ構造
Judith Schlagnitweit1, Mingxue Tang1, Maria Baias1
1Institut de Science Analytiques, Centre de RMN à très hauts champs, Université de Lyon , CNRS/ENS de Lyon/UCB Lyon1, 69100 Villeurbanne, France.
Journal of the American Chemical Society
|September 24, 2015
まとめ
ナノスケール領域の大きさを測定する 新しい核磁気共鳴法 (NMR) を開発しました この技術は 薬剤の放出を制御するために不可欠な 製薬コーティングの粒子の大きさを正確に決定します
科学分野:
- 材料科学
- ポリマー化学
- 分析化学
背景:
- 粒子やドメインの大きさによって 物質の性質が大きく影響されます
- ナノスケールの精密な測定は 医薬品や材料科学などの分野で重要です
- 既存の方法は,複雑な混合物内の特定のドメインサイズを解決する上で制限がある可能性があります.
研究 の 目的:
- ナノスケール長さの決定のための新しい核磁気共鳴 (NMR) のアプローチを導入し,検証する.
- 多成分ポリマーシステムにおけるドメインサイズを測定するためにこのNMR技術を適用する.
- 薬剤の制御放出剤におけるこの方法の有用性を評価する.
主な方法:
- NMRによるスピン拡散 (SD) によって伝達されたパラマグネティック・リラクゼーション・エンハンスメント (PRE) を使用した.
- ポリマー混合物の成分を 選択的にドーピングした
- 混合物の第二のドーピングされていない成分で測定されたドメインサイズ.
主要な成果:
- ナノメートルからマイクロメートルまでの長さを成功裏に決定した.
- エチルセルロース/ヒドロキシプロピルセルロースのフィルムコーティングの定量化ドメインサイズ
- 粒子の大きさは約50~200 nmの範囲内です
結論:
- SD NMR による PRE リレーは,ナノスケールのドメインサイズを測定するのに有効です.
- この技術は,ポリマー混合物の微細構造に関する貴重な洞察を提供します.
- このアプローチは製薬剤に適用され,制御放出システムの設計に役立ちます.
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