ハイアルロナンの水溶液における拡散定数の新しい距離依存は,その特徴的なナノ-マイクロ構造から生じる

A Masuda¹, K Ushida, H Koshino

¹RIKEN (The Institute of Physical and Chemical Research), Wako, Saitama 351-0198, Japan.

Journal of the American Chemical Society

|November 15, 2001

まとめ

ハイアルロナン (HA) 溶液中の物質輸送は,観測時間によって異なります. パルスフィールドグラデントNMRは,HAの影響を受けた長期的な拡散を明らかにします.

科学分野:

*ポリマー科学と物理化学

背景:

*ヒアルロノン (HA) は,複雑な溶液行動を持つ重要なバイオポリマーです.
* HA溶液における物質輸送の理解は,生物学的および工業的な応用に不可欠です.

研究の目的:

* ハイアルロナンの水溶液中の物質輸送を調査する.
*パルスフィールドグラデントNMR (PFG-NMR) と光化学的冷却によって得られた拡散測定値を比較する.
* HA溶液の微細構造が分子拡散に及ぼす影響を明らかにする.

主な方法:

* 長時間拡散測定のためにパルスフィールドグラデントNMR (PFG-NMR) を利用しました.
* 短時間拡散測定のための光化学的火を使用しています.
*両方の技術で同一の探査分子を使用しました.

主要な成果:

* PFG-NMRの拡散定数は,HA網によって著しく遅延した長距離輸送を反映しています.
* PFG-NMRと光化学的冷却の間の拡散値の顕著な相違は,異なる観測時間により観察されました.
*この研究は,不均質なHA溶液における拡散の時間依存性を強調しています.

結論:

*ポリマーネットワーク内のナノ〜マイクロスケールの毛穴を特徴とするヒアルロナンの溶液の微細構造が,拡散行動を決定する.
* 拡散定数は観測時間と結果の平均拡散距離に依存する.
* 拡散距離と毛孔の大きさの量的な比較により,HAネットワーク構造の役割が明らかになった.

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