Molecular Ratchets and Kinetic Asymmetry: Giving Chemistry Direction

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(23)

Published: April 3, 2024

Abstract Over the last two decades ratchet mechanisms have transformed understanding and design of stochastic molecular systems—biological, chemical physical—in a move away from mechanical macroscopic analogies that dominated thinking regarding dynamics in 1990s early 2000s (e.g. pistons, springs, etc), to more scale‐relevant concepts underpin out‐of‐equilibrium research sciences today. Ratcheting has established nanotechnology as frontier for energy transduction metabolism, enabled reverse engineering biomolecular machinery, delivering insights into how molecules ‘walk’ track‐based synthesisers operate, acceleration reactions enables be transduced by catalysts (both motor proteins synthetic catalysts), dynamic systems can driven equilibrium through catalysis. The recognition biology, their invention systems, is proving significant areas diverse supramolecular chemistry, covalent DNA nanotechnology, polymer materials science, heterogeneous catalysis, endergonic synthesis, origin life, many other branches science. Put simply, give chemistry direction. Kinetic asymmetry, key feature ratcheting, counterpart structural asymmetry (i.e. chirality). Given ubiquity processes significance behaviour function it surely just fundamentally important. This Review charts recognition, development ratchets, focussing particularly on role which they were originally envisaged elements machinery. Different kinetically asymmetric are compared, consequences discussed. These archetypal examples demonstrate inexorably equilibrium, rather than relax towards it.

Language: Английский

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Animating hydrogel knotbots with topology-invoked self-regulation

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Jan. 5, 2024

Abstract Steering soft robots in a self-regulated manner remains grand challenge, which often requires continuous symmetry breaking and recovery steps for persistent motion. Although structural morphology is found significant robotic functions, geometric topology has rarely been considered appreciated. Here we demonstrate series of knotbots, namely hydrogel-based with knotted structures, capable autonomous rolling spinning/rotating motions. With broken by external stimuli restored self-regulation, the coupling between self-constraint-induced prestress photothermal strain animates knotbots continuously. Experiments simulations reveal that nonequilibrium processes are regulated dynamically cooperatively self-constraints, active deformations, self-shadowing effect photo-responsive gel. The motions enable to execute tasks including gear rotation rod climbing. This work paves way devise advanced sustainable harnessing topology.

Language: Английский

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Kinetic Asymmetry and Directionality of Nonequilibrium Molecular Systems

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(9)

Published: Jan. 18, 2024

Abstract Scientists have long been fascinated by the biomolecular machines in living systems that process energy and information to sustain life. The first synthetic molecular rotor capable of performing repeated 360° rotations due a combination photo‐ thermally activated processes was reported 1999. progress designing different intervening years has remarkable, with several outstanding examples appearing last few years. Despite accomplishments, there remains confusion regarding fundamental design principles which motions molecules can be controlled, significant intellectual tension between mechanical chemical ways thinking about describing machines. A thermodynamically consistent analysis kinetics rotors pumps shows while light driven operate power‐stroke mechanism, kinetic asymmetry—the relative heights barriers—is sole determinant directionality catalysis Power‐strokes—the depths wells—play no role whatsoever determining sign directionality. These results, elaborated using trajectory thermodynamics nonequilibrium pump equality, show asymmetry governs response many non‐equilibrium phenomena.

Language: Английский

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Transducing chemical energy through catalysis by an artificial molecular motor

Nature, Journal Year: 2025, Volume and Issue: 637(8046), P. 594 - 600

Published: Jan. 15, 2025

Abstract Cells display a range of mechanical activities generated by motor proteins powered through catalysis 1 . This raises the fundamental question how acceleration chemical reaction can enable energy released from that to be transduced (and, consequently, work done) molecular catalyst 2–7 Here we demonstrate molecular-level transduction force 8 in form contraction and re-expansion cross-linked polymer gel driven directional rotation artificial catalysis-driven 9 motors. Continuous 360° rotor about stator motor-molecules incorporated polymeric framework twists chains network around one another. progressively increases writhe tightens entanglements, causing macroscopic approximately 70% its original volume. The subsequent addition opposite enantiomer fuelling system powers reverse direction, unwinding entanglements re-expand. Continued twisting strands new direction causes re-contract. In actuation, motor-molecule produces other physical outcomes, including changes Young modulus storage modulus—the latter is proportional increase strand crossings resulting rotation. experimental demonstration against load synthetic organocatalyst, mechanism 6 , informs both debate 3,5,7 surrounding generation biological motors design principles 6,10–14 for nanotechnology.

Language: Английский

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Photoresponsive Rotaxane-Branched Dendrimers: From Nanoscale Dimension Modulation to Macroscopic Soft Actuators

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(26), P. 14498 - 14509

Published: June 16, 2023

Aiming at the construction of novel soft actuators through amplified motions molecular machines nanoscale, design and synthesis a new family photoresponsive rotaxane-branched dendrimers an efficient controllable divergent approach was successfully realized for first time. In third-generation dendrimers, up to 21 azobenzene-based rotaxane units located each branch, thus making them successful light-control integrated artificial machines. Notably, upon alternative irradiation with UV visible light, photoisomerization azobenzene stoppers leads collective precisely arranged units, resulting in reversible dimension modulation integrating solution. Moreover, macroscopic were further constructed based on these which revealed fast shape transformation behaviors actuating speed 21.2 ± 0.2° s-1 ultraviolet irradiation. More importantly, resultant could produce mechanical work light control that has been employed weight-lifting cargo transporting, laying foundation toward smart materials can perform programmed events.

Language: Английский

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Artificial Molecular Ratchets: Tools Enabling Endergonic Processes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(47)

Published: Aug. 7, 2023

Abstract Non‐equilibrium chemical systems underpin multiple domains of contemporary interest, including supramolecular chemistry, molecular machines, prebiotic and energy transduction. Experimental chemists are now pioneering the realization artificial that can harvest away from equilibrium. In this tutorial Review, we provide an overview ratchets: mechanisms enabling absorption environment. By focusing on mechanism type—rather than application domain or source—we offer a unifying picture seemingly disparate phenomena, which hope will foster progress in fascinating science.

Language: Английский

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Ratcheting synthesis

Nature Reviews Chemistry, Journal Year: 2023, Volume and Issue: 8(1), P. 8 - 29

Published: Dec. 15, 2023

Language: Английский

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Formation of polyrotaxane crystals driven by dative boron–nitrogen bonds

Science Advances, Journal Year: 2023, Volume and Issue: 9(27)

Published: July 5, 2023

The integration of mechanically interlocked molecules (MIMs) into purely organic crystalline materials is expected to produce with properties that are not accessible using more classic approaches. To date, this has proved elusive. We present a dative boron–nitrogen bond-driven self-assembly strategy allows for the preparation polyrotaxane crystals. nature material was confirmed by both single-crystal x-ray diffraction analysis and cryogenic high-resolution low-dose transmission electron microscopy. Enhanced softness greater elasticity seen crystals than nonrotaxane polymer controls. This finding rationalized in terms synergetic microscopic motion rotaxane subunits. work thus highlights benefits integrating MIMs materials.

Language: Английский

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The paradigm for exceptional iodine capture by nonporous amorphous electron-deficient cyclophanes

Journal of Hazardous Materials, Journal Year: 2024, Volume and Issue: 465, P. 133449 - 133449

Published: Jan. 5, 2024

Language: Английский

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A Cost‐Effective Computational Strategy for the Electronic Layout Characterization of a Second Generation Light‐Driven Molecular Rotary Motor in Solution

Journal of Computational Chemistry, Journal Year: 2025, Volume and Issue: 46(2)

Published: Jan. 11, 2025

ABSTRACT Light‐driven molecular rotary motors are nanometric machines able to convert light into unidirectional motions. Several types of have been developed better respond stimuli, opening new avenues for developing smart materials ranging from nanomedicine robotics. They great importance in the scientific research across various disciplines, but a detailed comprehension underlying ultrafast photophysics immediately after photo‐excitation, that is, Franck–Condon region characterization, is not fully achieved yet. For this aim, it first required rely on an accurate description at ab initio level system potential energy before performing any further step, dynamics. Thus, we present extensive investigation aimed accurately describing electronic structure low‐lying states (electronic layout) rotor region, belonging class overcrowded alkenes: 9‐(2‐methyl‐2,3‐dihydro‐1H‐cyclopenta[a]naphthalen‐1‐ylidene)‐9H‐fluorene. This was chosen since its very interesting more general understanding similar compounds used as rotors, where can be found (whose energetic interplay crucial dynamics) and presence different substituents tune HOMO‐LUMO gap. scope, employed theory levels within time‐dependent density functional framework, presenting also careful comparison adopting post Hartree–Fock methods characterizing conformations involved photocycle. Effects layout functionals, basis sets, environment descriptions, role dispersion correction were all analyzed detail. In particular, treatment solvent effects here considered depth, showing how implicit excited by testing both linear‐response state‐specific formalisms. As main results, chose two cost‐effective (accurate relatively cheap) ground state verified choosing these influence curvature via frequency analysis normal modes vibrations active Raman spectrum. theoretical survey step towards feasible characterization early stage solution during photoisomerization processes wherein multiple might populated upon radiation, leading future molecular‐level interpretation time‐resolved spectroscopies.

Language: Английский

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