エタノール/水溶液中のイオンペアリングは,電泳性および拡散性NMRによって探査されました
Fredrik Hallberg1, István Furó, Peter Stilbs
1Division of Physical Chemistry and Industrial NMR Centre, Department of Chemistry, Royal Institute of Technology, SE-10044 Stockholm, Sweden.
Journal of the American Chemical Society
|September 11, 2009
まとめ
私たちは,溶液中のイオンペアリングを定量化するために,NMRスペクトロスコピーを用いた新しい方法を開発しました. このテクニックは,イオンペアリングに対するホフマイスター効果を明らかにし,二価イオンが単価イオンよりも強いペアリングを示す.
科学分野:
- 物理化学 物理化学
- 溶液化学について
- スペクトル顕微鏡検査です.
背景:
- イオンペアリングは,溶液の振る舞いを理解する上で極めて重要です.
- イオンペアリングを定量化することは困難です.
- ホフマイスター効果は,イオンがタンパク質の溶解性と他の性質にどのように影響するかを説明します.
研究 の 目的:
- 溶液中の平均イオン電荷を測定するための定量的な方法を開発する.
- この方法を用いてイオンペアリングを評価する.
- イオンペアリングに対するホフマイスター効果を調査するために.
主な方法:
- 結合電泳核磁共振 (NMR) と拡散NMR実験.
- 溶液中のイオンによって運ばれる平均電荷の測定.
- 95%エタノール/水溶液で分析されたイオンペアリング.
主要な成果:
- イオンペアリングを示すために平均イオン電荷を測定しました.
- 単価アニオンとテトラメチルアモニウムカチオン間のイオンペアリングにおけるホフマイスター関係が観察されました.
- 二価硫酸イオンが単価アニオンよりも強いイオンペアリングを示すことを発見した.
結論:
- エレクトロフォレティックおよび拡散型NMRは,イオンペアリングの定量的な測定を提供します.
- エタノール/水溶液におけるイオンペアリングは,ホフマイスターのトレンドに従う.
- 二価アニオンは,テトラメチルアモニウムカチオンを持つ単価アニオンよりも強いイオンペアを形成する.
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