News

Tiny origami controlled by light

Nanosized hinges can fold and unfold on command
DNA Hinge open without having light shone on it, and closing under illumination
DNA Hinge closes when light it shone one it (Aalto University/Anton Kuzyk)

Molecular machines are the incredibly small and powerful pieces of biology that power our bodies and most of the natural world. Despite being essential to all life on earth and having huge potential for revolutionising nanotechnology, humans are a way off being able to replicate them ourselves, because we lack the ability to control structures that are so small. In an attempt to develop this level of control, a team of chemists and bioengineers have made synthetic nanostructures that change shape on command.

To achieve this, they turned to a well-known molecule: DNA. As well as being useful for carrying genetic code, DNA can twist, fold, and take on many different shapes. The ability to fold DNA on command, referred to DNA origami, is an exciting step in the pursuit of making molecular machines. The team of researchers from Aalto University in Finland and the Weizmann institute in Israel have been able to make a structure like a hinge that opens and closes in a way that’s very simple to control. 

Hinges thousands of times thinner than hair

“The way it works is that the nano-hinges are in a solution that becomes more acidic when light is shone on it. The increasing acidity of the solution causes chemical bonds to form in the hinges that link the ends together, thus pulling the hinge closed,” said Joonas Ryssy, first author of the paper. “When the light is turned off, the acidity of the solution reverses, causing the bonds between the ends to break, and the hinge opens up again.”

The results have been published in Angewandte Chemie and builds upon previous work from the same group on manipulating macromolecules. Using light to tune the configuration of the DNA origami is appealing because light is easy to control and can be done remotely. Researchers have previously struggled to add light-responsive control to DNA structures, but the trick with this work was coupling the light-responsive solution with the acid-responsive DNA macromolecules.

Fine control 

“We can control the tendency of DNA origami hinges to close or open by the amount of light we shine on them,” explains Anton Kuzyk, a Professor in the department of neuroscience and biomedical engineering at Aalto University. “If we don’t want all hinges to be closed, we don’t shine as much light on them. This level of control is an exciting property of our system that marks it out from others.” As well as having gradient control over the degree of folding, the process is repeatable. If the light is turned back on, the origami folds again. 

“Whereas similar light-responsive systems need one light source to close the joint, they also require another to open it back up again,” says Professor Rafal Klajn at the Weizmann Institute. “Our system only needs one light source, making it potentially more useful for future applications.”

Further Information

Full paper: Light-Responsive Dynamic DNA-Origami-Based Plasmonic Assemblies, DOI: https://doi.org/10.1002/anie.202014963

Contact

Anton Kuzyk
Professor
[email protected]

  • Published:
  • Updated:
Share
URL copied!

Related news

Taiteellinen kuva panssaroidusta superhydrofobisesta pinnasta, joka kestää iskuja ja hylkii nesteitä tehokkaasti. Kuva: Juha Juvonen.
Cooperation, Press releases, Research & Art Published:

New funding to commercialise high-tech liquid-repelling coatings

New funding to get damage-resistant, liquid-repelling surfaces out of the laboratory and onto solar panels, skis, and more
The computer game could help in the treatment of depression alongside therapy and drug treatment. Picture: Matias Palva’s research group, Aalto University.
Press releases Published:

Researchers developing computer game to treat depression

Playing a therapeutic action game can ease symptoms in patients with depression, and improve their cognitive performance
An electron microscope image of the device used to extract entangled electrons
Press releases Published:

Entangling electrons with heat

Entanglement is key for quantum computing and communications technology; Aalto researchers can now extract entangled electrons using heat
Ihminen tekemässä työtä laboratotiossa.
Press releases, Research & Art Published:

How to motivate people to comply voluntarily with necessary restrictions – 13 principles for effective COVID-19 related communication

Decision-makers and experts should support people's autonomy, competence and relatedness in their COVID-19 related communications with citizens.