水动力学从表面到超分子纳米结构的内部
Julia H Ortony, Baofu Qiao1, Christina J Newcomb1
1Department of Materials Science and Engineering, §Department of Chemistry, ⊥Department of Chemical and Biological Engineering, and∇Department of Biomedical Engineering, Northwestern University , Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|June 22, 2017
概括
纳米级材料附近的水动力学对于细胞事件至关重要. 这项研究揭示了纳米纤维内明显的水运动,
科学领域:
- 生物物理
- 材料科学
- 纳米技术
背景情况:
- 细胞过程依赖于水分子与生物分子结构相互作用的独特动态.
- 水与生物分子之间的接口决定了水的行为, 并影响了蛋白质折叠等生物事件.
- 了解纳米级的水力学是设计用于生物应用的功能纳米材料的关键.
研究的目的:
- 在超分子纳米纤维中研究水分子的转化动力学.
- 探索纳米纤维的纳米环境如何影响水的结构和运动.
- 阐明介面水在纳米级生物材料的功能中的作用.
主要方法:
- 使用Overhauser动态核极化 (DNP) 放松计的实验调查.
- 分析水分子动态的计算建模.
- 在6.7nm直径的纳米纤维中描述水的行为.
主要成果:
- 在纳米纤维表面大约1nm内观察到水运动的显著差异.
- 在纳米纤维的疏水内部检测到水分子的快速扩散.
- 在纳米纤维表面的水分子表现出固定或显著限制的运动.
结论:
- 与纳米级材料相关的水不仅仅是被动溶剂,而且是材料结构的活性成分.
- 纳米纤维中的独特水动力学表明了量身定制的界面特性.
- 这些发现强调了在生物系统中纳米材料的设计和功能中考虑水的重要性.
相关概念视频
Surface Tension of Fluid
1.8K
Surface tension is a fundamental property of fluids, occurring at the boundary between a liquid and a gas or between two immiscible liquids. This phenomenon arises from the cohesive forces between molecules at the fluid's surface, creating an effect similar to a stretched elastic membrane. Inside each fluid, molecules are equally attracted in all directions by neighboring molecules, but surface molecules experience a net inward force, resulting in surface tension.
Surface tension varies...
Surface tension varies...
1.8K
Intermolecular Forces
74.1K
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen...
74.1K
Theories of Dissolution: The Danckwerts' Model and Interfacial Barrier Model
876
Various dissolution theories provide insight into the factors that influence the dissolution rate. Danckwerts' Model suggests that turbulence, rather than a stagnant layer, characterizes the dissolution medium at the solid-liquid interface. In this model, the agitated solvent contains macroscopic packets that move to the interface via eddy currents, facilitating the absorption and delivery of the drug to the bulk solution. The regular replenishment of solvent packets maintains the...
876
Surface Tension, Capillary Action, and Viscosity
33.9K
Surface Tension
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
33.9K
Intermolecular Forces in Solutions
40.4K
The formation of a solution is an example of a spontaneous process, a process that occurs under specified conditions without energy from some external source.
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Such a solution is called an ideal solution. A mixture of ideal gases (or gases such as helium and argon,...
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Such a solution is called an ideal solution. A mixture of ideal gases (or gases such as helium and argon,...
40.4K
Cohesion
60.2K
Cohesion is the attraction between molecules of the same type, such as water molecules. Water molecules have an overall neutral charge but are polar molecule. An oxygen atom in one water molecule has a partial negative charge that can bind to a hydrogen atom with a partial positive charge in a second water molecule, forming a hydrogen bond. Each water molecule can form up to four hydrogen bonds with other water molecules. Hydrogen bonds are responsible for water's cohesive nature.
On a...
On a...
60.2K


