磁性ナノセンサと標的の間のアセンブリ状態は,磁性リラックス反応をオーケストラ化する
Charalambos Kaittanis1, Santimukul Santra, Oscar J Santiesteban
1Nanoscience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, Florida 32826, United States.
Journal of the American Chemical Society
|February 24, 2011
まとめ
研究者らは,新しい磁性ナノ粒子相互作用を発見し,NMRリラクゼーション時間 (T2) を増加させ,DNA,タンパク質,がん細胞などの標的の感度のある検出を可能にしました. この新しいメカニズムは,臨床応用のためのより速い運動性を提供します.
科学分野:
- ナノテクノロジー ナノテクノロジー
- バイオメディカルエンジニアリング
- アナリティカル・ケミストリー (Analytical Chemistry) とは
背景:
- 磁性ナノ粒子 (MNP) は,通常,標的検出のためのクラスタリングを通じてT2減少を誘導します.
- 従来のMNPアッセイは,ターゲット誘発のクラスタリングに依存し,水プロトンの横断リラクゼーション時間が短縮される (T(2)).
研究 の 目的:
- 新しいMNP-ターゲットの相互作用メカニズムを発見し,特徴づけること.
- MNP-リガンド相互作用でT(2) が増加し,r(2) のリラクシビティが減少することを実証する.
- 繊細な生物分子検出のためのこの新しいメカニズムの可能性を調査する.
主な方法:
- 小分子,タンパク質,核酸の化学結合で,ポリアクリル酸でコーティングされた酸化鉄ナノ粒子に.
- 水プロトンの横断NMRリラクゼーション時間 (T(2) とリラクシビティ (r(2) の測定.
- 異なった標的濃度とリガンド形態 (モノマー対ペンタマー) を使って,メカニズム移行を研究する.
主要な成果:
- 新しいMNP-ターゲットの相互作用が特定され,T(2) が増加し,r(2) が減少しました.
- r(2) の減少は,リガンド数と分子量に反比例した.
- バシルス・アントラシスのDNA (5.3 fmol),コレラ毒素Bサブユニット (8 pmol),がん細胞の感受性検出が達成されました.
- 結合からクラスタリングへのメカニズムの移行は,標的濃度またはペンタメリックCtb.の増加とともに観察されました.
結論:
- MNP-ターゲットの相互作用の分子構造は,NMRの緩和を決定する.
- 観測されたT(2) の増加は,水の拡散を阻害するバインドされたターゲットに起因する.
- この新しい,より高速なMNP相互作用メカニズムは,新しい臨床およびフィールド検出アプリケーションの有望性を示しています.
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