化学交換飽和転移剤としてアルコールのペンダントグループを持つユーロピウム (III) マクロサイクル複合体
Mark Woods1, Donald E Woessner, Piyu Zhao
1Macrocyclics, 2110 Research Row, Suite 425, Dallas, Texas 75235, USA.
Journal of the American Chemical Society
|August 3, 2006
まとめ
パラ磁性ランタニド複合体は,MRIコントラスト剤として有望であることが示されています. しかし,ヒドロキシエチル基を持つユーロピウム (III) 複合体は,小さな化学的シフトと急速な水交換のために,限られた有用性を持っています.
科学分野:
- マグネティックレゾーナンスイメージング (MRI)
- 無機化学 無機化学とは
- バイオメディカルエンジニアリング
背景:
- 交換可能な陽子を持つパラ磁性ランタニド ((III)) 複合体は,二磁性分子と比較して,MRIのための有利な化学交換飽和移転 (CEST) 剤です.
- これらのCEST剤の感受性を高める方法を調査することは,MRIアプリケーションの進歩に不可欠です.
研究 の 目的:
- ヒドロキシエチル基で機能したユーロピウム (III) マクロサイクル複合体のCEST特性を調査する.
- これらの複合体のMRIコントラスト剤としての可能性を評価する.
主な方法:
- 添付されたヒドロキシエチル基を持つユーロピウム (III) マクロサイクリック複合体の合成と特徴付け.
- NMRブロック理論を用いたCESTスペクトルの分析により,陽子の交換率を決定する.
- アセトニトリル溶液に水を加え,陽子交換への影響を研究する.
主要な成果:
- 非対称的な複合体EuCNPHC3+は,CESTスペクトルでプロトンプールごとに5つの異なるピークを示した.
- Eu3+に結合したヒドロキシル群と大量水間の陽子交換は,乾燥アセトニトリルでは遅く,水添加で増加した.
- 純粋な水では,陽子交換があまりにも速く,CEST効果が観察できませんでした.
結論:
- これらのエウロピウム (III) 複合体のCEST画像の有用性は,ヒドロキシエチルリガンドからの限られた化学的シフトによって制限されています.
- 交換可能なヒドロキシル陽子の小さなデルタオメガ値は,CEST MRIにおけるその適用をさらに制限する.
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