ダイナミックな核極化のための水溶性狭線線素
Olesya Haze1, Björn Corzilius, Albert A Smith
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|August 25, 2012
まとめ
研究者らは,ダイナミックな核極化 (DNP) のための新しい水溶性有機基素を開発した. これらのBDPAベースの薬剤は,NMRにおける有意な感受性向上を提供し,極化剤技術の進歩をもたらします.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 磁気共振スペクトロスコピー 磁気共振スペクトロスコピー
- マテリアルサイエンス 材料科学
背景:
- ダイナミック・ニュクレア・ポラライゼーション (DNP) は,偏光剤を用いてNMRの感受性を高めます.
- トリチルラジカルのような既存の狭い線極化剤には限界があります.
- 安定した,水溶性有機ラジカルの開発は,より広範なDNPアプリケーションに不可欠です.
研究 の 目的:
- 1,3-ビス・ディフェニレン・2フェニラリル (BDPA) コアを基に,空気に安定し,水に溶ける有機ラジカルを合成し,特徴づけること.
- 固体効果DNP (SE DNP) の極化剤として硫化誘導体 (SA-BDPA) の性能を評価する.
- BDPAベースのラジカルの有効性を既存のトリチル型剤と比較する.
主な方法:
- BDPAコアおよびその硫化デリバティブ (SA-BDPA) の合成.
- 電子パラマグネティック共振 (EPR) スペクトロスコピーは,線幅を決定する.
- 固体効果ダイナミック核極化 (SE DNP) 実験.
- 感度増強測定のための高場マジック・アングル・スピニング (MAS) 核磁気共鳴 (NMR) スペクトロスコピー.
主要な成果:
- 空気に安定し,水に溶けやすいBDPAベースの有機ラジカルを成功に合成しました.
- SA-BDPAは,濃縮溶液で狭いEPRライン幅 (5Tで<30MHz) を実証しました.
- SA-BDPAを使用した高フィールドMAS NMR実験で110の感度向上を達成しました.
- BDPAベースのラジカルは,合成の容易さと高い最大増強を示しました.
結論:
- BDPAベースの有機根幹,特にSA-BDPAは,SE DNPの効果的な分極剤である.
- これらの新種のラジカルは,合成と性能の観点から,トリチル型剤に比べて有意な利点を提供しています.
- 開発されたラジカルは,高フィールドNMRスペクトロスコピーの材料における大きな進歩を表しています.
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