The first chemically fueled small-molecule walker dances around a sugar molecule without falling off

Photoswitches that affect π-conjugation offer a powerful strategy for external manipulation of luminescent diradicals. Dithienylethene-linked persistent trityl diradicaloids, DTE-TTM2 and F6-DTE-TTM2....

No need for metals or recognition sites to build these molecular machines

We demonstrate the near-quantitative formation of an imine bond in water under physiologically relevant conditions using a stoichiometric ratio of aldehyde and amine. To overcome the low hydrolytic stability of imines in water, a complementary metal coordination bond between the amine and aldehyde monomers is introduced to enhance the thermodynamic stability of the imine. Imine bond formation is substrate-selective, tolerates the presence of a variety of functional groups, and produces imines that are stable in a broad pH range. We also show that the presence of a second metal-ion complex in the building blocks provides a regulatory handle to ‘switch on’ imine-bond formation using ATP as an external allosteric effector.

The structural anisotropy necessary for the powered directional rotation of chemically fuelled molecular motors had previously been provided by chiral fuels or enzymes. Now it has been shown that asym...

Molecular machine properties such as speed, efficiency, power, and torque depend upon particular features of structure, mechanism, and chemistry. The graphical abstract shows a Top Trumps-style representation of key performance indicators, illustrating how the first generation of synthetic catalysis-driven small-molecule machines compare with their biomolecular analogs. The understanding of how molecular machine design affects properties should aid technological advancements and a deeper understanding of the fundamental principles that link physics, chemistry, and biology.

Nature Nanotechnology, Published online: 19 September 2025; doi:10.1038/s41565-025-01997-yIn a non-equilibrium environment, molecular machines can undergo a directed flow through configurational changes, a feature that is widely exploited in processes characteristic of life. The use of such a flow to enhance the specificity of molecular recognition beyond equilibrium conditions has now been demonstrated in a minimal, synthetic, DNA-based system.

A merocyanine-based amphiphile self-assembles in water to form visible-light-responsive ellipsoids that can be disassembled with visible light and reform abruptly ∼70 minutes after the light is switc...

An abiotic information ratchet mechanism increases selectivity for the correct DNA duplex from 2:1 at equilibrium to 6:1 under energy-dissipating conditions.

We report the in situ quantification of directional rotation of a new type of catalysis-driven rotary motor featuring a phenyl carboxylic acid rotor attached to a 7-azaindole-N-oxide stator through a biaryl C–N bond. Continuous directional rotation of the rotor about the stator is driven by the achiral motor’s rotary catalysis of carbodiimide hydration in the presence of a chiral pyrrolidinylpyridine-N-oxide. The catalytic cycle features an intermediate O-acyl-azaindole-N-oxide ester tether formed between the carboxylic acid of the rotor and the N-oxide of the stator. Face-selective cleavage of the tether by the chiral pyrrolidinylpyridine-N-oxide additive generates relatively long-lived diastereomeric pyridine-N-oxide esters of the phenyl carboxylic acid. These are hydrolyzed during the catalytic cycle to reform the carboxylic acid resting state of the motor, completing net directional 360° rotation. In contrast to previous catalysis-driven motor-molecules, the motor’s directionality could be determined directly from the transient concentrations of the diastereomeric intermediates formed during rotary catalysis. This avoids reliance on restricted rotation models to assess motor directionality and provides direct access to other key performance indicators such as motor speed and catalytic, coupling and fuel efficiency. The in situ-determined directionality of the motor was found to be in excellent agreement with the directionality determined from a restricted rotation model, supporting both the efficacy of the new approach and the validity of using appropriately designed restricted rotation models. The results establish a straightforward method for the in situ quantification of various aspects of motor behavior, aiding the design and optimization of artificial molecular motors.

This paper examines the temperature-mortality relationship over the course of the 20th century US both for its own interest and to identify potentially useful a

Le ministre de la recherche a dit sa « préoccupation », mercredi, après cette décision des autorités américaines. Le chercheur du CNRS aurait subi un contrôle aléatoire à son arrivée, avant que son or...

Some things are changing rather fundamentally and the way we think should perhaps change too

Continuous directionally biased 360° rotation about a covalent single bond was recently realized in the form of a chemically fueled 1-phenylpyrrole 2,2′-dicarboxylic acid rotary molecular motor. However, the original fueling system and reaction conditions resulted in a motor directionality of only ∼3:1 (i.e., on average a backward rotation for every three forward rotations), along with a catalytic efficiency for the motor operation of 97% and a fuel efficiency of 14%. Here, we report on the efficacy of a series of chiral carbodiimide fuels and chiral hydrolysis promoters (pyridine and pyridine N-oxide derivatives) in driving improved directional rotation of this motor-molecule. We outline the complete reaction network for motor operation, composed of directional, futile, and slip cycles. Using derivatives of the motor where the final conformational step in the 360° rotation is either very slow or completely blocked, the phenylpyrrole diacid becomes enantiomerically enriched, allowing the kinetic gating of the individual steps in the catalytic cycle to be measured. The chiral carbodiimide fuel that produces the highest directionality gives 13% enantiomeric excess (e.e.) for the anhydride-forming kinetically gated step, while the most effective chiral hydrolysis promoter generates 90% e.e. for the kinetically gated hydrolysis step. Combining the best-performing fuel and hydrolysis promoter into a single fueling system results in a 92% e.e.. Under a dilute chemostated fueling regime (to avoid N-acyl urea formation at high carbodiimide concentrations with pyridine N-oxide hydrolysis promoters), the motor continuously rotates with a directionality of ∼24:1 (i.e., a backward rotation for every 24 forward rotations) with a catalytic efficiency of >99% and a fuel efficiency of 51%.

Societies should learn from this and speak up to support inclusion

Donate to the Wikimedia Foundation, the nonprofit that hosts Wikipedia and other crucial free knowledge projects. Each year, the generosity of the 2% of readers who donate allows us to expand the reac...

We're an interdisciplinary research group led by Dr Stephen Fielden within the School of Chemistry at the University of Birmingham. We research polymers, nanoparticles and supramolecular chemistry.

A cross-linked polymer gel driven by artificial molecular motors transforms chemical energy into mechanical force, achieving powered contraction and re-expansion, demonstrating a considerable advance in understanding energy transduction mechanisms and informing nanotechnology design principles.

There's a lot more lab work to do before we understand the 'language of life'

For several decades, molecular motor directionality has been rationalized in terms of the free energy of molecular conformations visited before and after the motor takes a step, a so-called power stroke mechanism with analogues in macroscopic engines. Despite theoretical and experimental demonstrations of its flaws, the power stroke language is quite ingrained, and some communities still value power stroke intuition. By building a catalysis-driven motor into simulated numerical experiments, we here systematically report on how directionality responds when the motor is modified accordingly to power stroke intuition. We confirm that the power stroke mechanism generally does not predict motor directionality. Nevertheless, the simulations illustrate that the relative stability of molecular conformations should be included as a potential design element to adjust the motor directional bias. Though power strokes are formally unimportant for determining directionality, we show that practical attempts to alter a power stroke have side effects that can in fact alter the bias. The change in the bias can align with what power stroke intuition would have suggested, offering a potential explanation for why the flawed power stroke mechanism can retain apparent utility when engineering specific systems.

At jobs.ac.uk, you can apply for a PhD Studentship: Mechanically Interlocked Biomolecules and Biomaterials for Drug Delivery Applications. Explore our diverse range of PhD opportunities today.

The development of active matter requires the ability to design materials capable of harnessing energy from a source to carry out work. Nature achieves this using chemical reaction cycles in which en....