液体滴における素早い水素-デウテリウム交換
Erik T Jansson1,2, Yin-Hung Lai2, Juan G Santiago3
1Department of Chemistry-BMC, Uppsala University , SE-751 24 Uppsala, Sweden.
Journal of the American Chemical Society
|May 9, 2017
まとめ
この研究では,質量スペクトロメトリーを用いて水滴の水素-デュテリウム交換率 (HDX) を測定し,大量溶液と比較して水滴のHDXが著しく加速したことが判明した. この技術は分子ダイナミクスを研究するためにミリ秒未満の解像度を提供します.
科学分野:
- 分析化学
- 物理化学
- 生物物理化学
背景:
- 水素-デュテリウム交換 (HDX) は,分子動力学と構造を研究するための重要な技術です.
- ストップフロー運動学やNMRスペクトロスコピーのような伝統的な方法は,迅速な交換プロセスにおける時間解像度に制限があります.
- HDXをマイクロドロップルで調べることで 高時間解像度で急速な化学反応を検出する 新しい方法が生まれます
研究 の 目的:
- フェネチラミンの水滴における水素-デウテリウム交換率 (HDX) を,ミリ秒未満の時間解像度で測定する.
- HDX率に対するドロップレット収束と微小環境の影響を調査する.
- 液滴のHDX値と溶液で測定されたHDX値を比較する.
主な方法:
- 水滴を生成するために,テータ毛細血管によるナノエレクトロスプレーイオン化を使用した.
- HDXの時間解像度をミリ秒以下で測定した.
- マイクロ粒子画像速度測定法で測定したマイクロドロップレットの速度.
- 普通の微分方程式を用いて HDX 運動をモデル化した.
主要な成果:
- 大量測定と比較して,水滴のHDX率の加速が観察されました.
- フェネチアミンHDXの速度定数は,−NH2D+形成の3660 ± 290 s−1,−NH2D+形成の3330 ± 270 s−1 である.
- 大量溶液と比較して 血管新生素IのHDXが 7倍増加しました
- 移動時間中に約30%のドロップレット加速が実証された.
結論:
- HDXは散布溶液よりも水滴で著しく速く発生し,閉じ込め効果が反応速度に影響することを示唆しています.
- テータ毛細血管法により,高速交換プロセスの迅速な混合と高通量分析が可能である.
- この技術は,前例のない時間的な解像度で分子動力学と運動学を研究するための強力なツールを提供します.
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