単一壁の炭素ナノチューブ上の表面吸収DNAのイオン強度媒介相変異
Daniel P Salem1, Xun Gong1, Albert Tianxiang Liu1
1Department of Chemical Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|October 21, 2017
まとめ
イオン強さは,DNAで包まれた単一壁の炭素ナノチューブ (SWCNTs) の可逆相転換を誘発し,その光性を大幅に変化させます. この基本的な相互作用はDNA吸収とSWCNTのコロナ特性に影響します.
科学分野:
- 材料科学
- ナノテクノロジー
- バイオ物理学
背景:
- 単一鎖DNA (ssDNA) と炭素ナノチューブ (CNT) の相互作用は複雑で配列に依存しています.
- これらの相互作用を理解することは,CNTベースのナノデバイスの開発に不可欠です.
研究 の 目的:
- シングルウォールカーボンナノチューブ (SWCNT) に吸収されたオリゴヌクレオチドの一般的,イオン強度介在の相変異を調査する.
- DNA-SWCNTの相互作用と環境要因と光学的性質を結びつける定量モデルを開発する.
主な方法:
- 25以上の異なるオリゴヌクレオチドをSWCNTに吸収する.
- 単価塩 (500 mMから1 mM) を使用してイオン強度の調節.
- 光量子収量変化,pH効果,そして溶けた酸素の存在の分析.
主要な成果:
- リバーシブルな相変化が観察され,光量子収量が最大90%減少した.
- DNAの表面覆いは,2つの状態の均衡モデルによって記述されるイオン強度に依存する.
- サイトシンプロトネーションはDNA結合に影響し,移行はSWCNTコロナフェーズとリボフラビン認識を調節する.
結論:
- 定量的モデルはDNA-SWCNTの光学特性をイオン強度,pH,酸素,アスコルビック酸と成功裏に結びつける.
- DNAとSWCNTの分子相互作用に関する基本的な洞察を得ることができます.
- この発見は,DNA-SWCNTシステムを用いた分子検知,アセンブリ,およびナノ粒子分離に意味を持つ.
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