Molecular propeller is a molecule that can propel fluids when rotated, due to its special shape that is designed in analogy to macroscopic propellers: it has several molecular-scale blades attached at a certain pitch angle around the circumference of a shaft, aligned along the rotational axis.
The molecular propellers designed in the group of Prof. Petr Král from the University of Illinois at Chicago have their blades formed by planar aromatic molecules and the shaft is a carbon nanotube. Molecular dynamics simulations show that these propellers can serve as efficient pumps in the bulk and at the surfaces of liquids. Their pumping efficiency depends on the chemistry of the interface between the blades and the liquid. For example, if the blades are hydrophobic, water molecules do not bind to them, and the propellers can pump them well. If the blades are hydrophilic, water molecules form hydrogen bonds with the atoms in the polar blades. This can largely block the flow of other water molecules around the blades and significantly slow down their pumping.
Molecular propellers can be rotated by molecular motors that can be driven by chemical, biological, optical and electrical means, or various ratchet-like mechanisms. Nature realizes most biological activities with a large number of highly sophisticated molecular motors, such as myosin, kinesin, and ATP synthase. For example, rotary molecular motors attached to protein-based tails called flagella can propel bacteria.
In a similar way, the assembly of a molecular propeller and a molecular motor can form a nanoscale machine that can pump fluids or perform locomotion. Future applications of these nanosystems range from novel analytical tools in physics and chemistry, drug delivery and gene therapy in biology and medicine, advanced nanofluidic lab-on-a-chip techniques, to tiny robots performing various activities at the nanoscale or microscale.
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Living organisms evolve in a physical world: their cells respond to mechanics, electricity and light. In this course, we will describe the behavior and function of cells using physical principles.
Telomere biology.
The students will obtain theoretical and practical insight into telomere biology and the roles of telomeres during cellular senescence and for genome stability.
Synthetic molecular motors are molecular machines capable of continuous directional rotation under an energy input. Although the term "molecular motor" has traditionally referred to a naturally occurring protein that induces motion (via protein dynamics), some groups also use the term when referring to non-biological, non-peptide synthetic motors. Many chemists are pursuing the synthesis of such molecular motors. The basic requirements for a synthetic motor are repetitive 360° motion, the consumption of energy and unidirectional rotation.
Un moteur moléculaire est un objet de la taille d’une molécule ou d’un assemblage de molécules qui est capable de produire un travail mécanique ou un mouvement dirigé, ces buts ne pouvant être atteints que si de l’énergie est fournie au système. Les différences les plus importantes par rapport aux moteurs macroscopiques concernent la sensibilité des moteurs moléculaires à la viscosité de leur micro-environnement, et surtout à l’importance de l’agitation thermique.
Explore la Synthase ATP de type F, une machine moléculaire cruciale pour la production d'énergie dans les cellules, couvrant sa structure, ses fonctions et ses mécanismes de production d'énergie.
Plonge dans la chimie supramoléculaire, en se concentrant sur les machines et les moteurs moléculaires, en explorant les principes de conception et le soutien expérimental pour le mouvement contrôlé.
Couvre les bases de la chimie supramoléculaire, y compris les processus d'auto-assemblage et les interactions moléculaires telles que la liaison hydrogène et les interactions cations-.
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Electrohelicity arises in molecules such as allene and spiropentadiene when their symmetry is reduced and helical frontier molecular orbitals (MOs) appear. Such molecules are optically active and electrohelicity has been suggested as a possible design prin ...
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