切り替え可能なモビリティを持つ指向された単一分子の拡散は,長い1次元のナノチャネルのネットワークで行われる

Christophe Jung¹, Johanna Kirstein, Barbara Platschek

¹Department of Chemistry und Biochemistry and Center for Nanoscience, Ludwig-Maximilians-Universität München, Butenandtstrasse 11, D-81377 München, Germany.

Journal of the American Chemical Society

|January 16, 2008

まとめ

単一の染料分子は,メソポラス膜の構造とダイナミクスを明らかにします. クロロフォーム中の彼らの動きは,単純な1Dランダムな動きではなく,欠陥と複雑な拡散を示しています.

科学分野:

マテリアルサイエンス材料科学
ナノテクノロジーナノテクノロジー
物理化学物理化学について

背景:

メソポラスマトリックス内の単一の染料分子は,敏感な環境レポーターとして機能します.
構造ドメインを持つ六角形のメソポラスフィルムが研究されました.
TDI (テトラセンの誘導体) 分子はゲストプローブとして使用されました.

研究の目的:

単一のTDI分子を使用して,メソポラスフィルムにおける構造ドメインのサイズをマッピングする.
宿主物質内のTDI分子のトランスレーションと指向のダイナミクスを調査する.
メソポラス宿主物質に関する構造的,動的情報を得るために.

主な方法:

単一のTDI分子を六角形のメソポラスフィルムに組み込む.
ダイナミクスを調査するための単一分子光技術.
高精度ポジショニング測定 (2-3 nm 精度).

主要な成果:

TDI分子は,100マイクロメートルを超える領域サイズをマッピングしました.
空気中では,TDI分子は動きを示せず,毛穴方向に沿って方向づけられました.
クロロフォームム蒸気では,隣接するチャネル間のTDI拡散が観察され,欠陥が明らかになりました.
拡散分析は,吸収部位による1Dランダム拡散を超えた複雑な振る舞いを示した.

結論:

単一分子探査機は,メソポラス材料の詳細な構造的および動的洞察を提供します.
メソポラス膜構造には,死角やチャネル間の開口などの欠陥が含まれています.
TDIの拡散は,吸収部位によって影響を受け,理想的でない拡散ダイナミクスにつながります.

さらに関連する動画

09:36

Study of Cell Migration in Microfabricated Channels

Published on: February 21, 2014

08:00

DNA Nanotubes as a Versatile Tool to Study Semiflexible Polymers

Published on: October 25, 2017

関連する概念動画

01:12

Diffusion

Diffusion is the passive movement of substances down their concentration gradients—requiring no expenditure of cellular energy. Substances, such as molecules or ions, diffuse from an area of high concentration to an area of low concentration in the cytosol or across membranes. Eventually, the concentration will even out, with the substance moving randomly but causing no net change in concentration. Such a state is called dynamic equilibrium, which is essential for maintaining overall...

01:21

Diffusion

Diffusion is a type of passive transport. In passive transport, a substance tends to move from an area of high concentration to an area of low concentration until the concentration is equal across the space. For example, take the diffusion of substances through the air. When someone opens a perfume bottle in a room filled with people, the perfume is at its highest concentration in the bottle and is at its lowest at the edges of the room. The perfume vapor will diffuse, or spread away, from the...

01:24

Protein Diffusion in the Membrane

Proteins show rotational as well as lateral diffusion across the membrane. The lateral diffusion of proteins was confirmed through the cell fusion experiment where mouse and human cells were fused, resulting in hybrid cells. When the human and mouse cells fused, the specific membrane proteins on human and mouse cells were marked with the red and green-fluorescent markers, respectively. Initially, the red and green fluorescence was located on the respective hemisphere of the cell. As time...

01:19

Facilitated Transport

The chemical and physical properties of plasma membranes cause them to be selectively permeable. Since plasma membranes have both hydrophobic and hydrophilic regions, substances need to be able to transverse both regions. The hydrophobic area of membranes repels substances such as charged ions. Therefore, such substances need special membrane proteins to cross a membrane successfully. In facilitated transport, also known as facilitated diffusion, molecules and ions travel across a membrane via...

01:19

Facilitated Transport

01:16

Facilitated Diffusion

The plasma membrane, a critical structure in cellular biology, houses an array of transporters, or carrier proteins, interspersed within its lipid bilayer. These proteins play a crucial role in solute transport through facilitated diffusion, a form of passive diffusion that uses transporters to move the molecules across the membrane.
In this process, substrates such as organic compounds and ions interact with a transporter on one side, triggering conformational changes in proteins that enable...

関連する実験動画