水素結合物質の粘着摩擦による摩擦
Aykut Erbaş1, Dominik Horinek, Roland R Netz
1Physik Department, Technische Universität München, 85748 Garching, Germany.
Journal of the American Chemical Society
|November 22, 2011
まとめ
生物学的物質のための新しい摩擦法則は,摩擦力が水素結合 (HBs) の数と滑り速度に比例することを明らかにします. この発見は,ナノスケールでの生体分子相互作用を理解するために極めて重要です.
科学分野:
- バイオフィジックス 生物物理学
- マテリアルサイエンス 材料科学
- トリボロジー トリボロジ トリボロジー
背景:
- マクロスコープ摩擦は,アモントンの法則でよく説明されています.
- 生物学的スケールでの生物学的マクロモレキュルのための同様の法則は欠けている.
- 水素結合 (HBs) は,生物分子相互作用において極めて重要です.
研究 の 目的:
- 低速度で水素結合生物物質の摩擦法則を確立するために.
- 生物学的長さおよび速度スケールでの摩擦における水素結合の役割を調査する.
主な方法:
- 表面に滑るペプチド鎖の原子学的分子ダイナミクスシミュレーション.
- 摩擦係数を決定するためにストキャスティックモデルを用いたエクストラポレーション.
- 水素結合と滑り速度に対する摩擦力の依存性の分析.
主要な成果:
- 摩擦力は,HBSの数と滑り速度に比例する.
- 約10−8 kg/sの摩擦係数 γ(HB) が決定されました.
- 協力的効果が観察され,約3つのHBが集団的に行動した.
結論:
- 低速度粘性状態における水素結合物質の単純な摩擦法則が実証されました.
- この法則は,様々なペプチド,表面の極性,および正常力に対して適用されます.
- 単一のHBの摩擦は,マイクロメートルの球体のストークス摩擦に相当します.
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