DNA robots designed in minutes instead of days

One day, scientists believe, small DNA-based robots and other nanodevices will deliver drugs into our bodies, detect the presence of deadly pathogens and help make smaller and smaller electronics.

Researchers have taken a big step toward that future, developing a new tool that can design much more complex robots and DNA nanodevices than have ever been possible in a fraction of the time.

In a paper published today in the journal Materials for nature, researchers at Ohio State University – led by former doctoral engineer Chao-Min Huang – have unveiled a new software they call MagicDNA.

The software helps researchers design ways to take small strands of DNA and combine them into complex structures with parts such as rotors and hinges that can move and complete a variety of tasks, including drug delivery.

Researchers have been doing this for several years with slower instruments, with tiring manual steps, said Carlos Castro, co-author of the study and associate professor of mechanical and aerospace engineering in Ohio.

“But now, nanodevices that could have taken us a few days to design so far only take us a few minutes,” Castro said.

And now researchers can make nanodevices much more complex and useful.

“Previously, we could build devices with up to six individual components and connect them to joints and hinges and try to make them perform complex movements,” said study co-author Hai-Jun Su, a professor of mechanical and aerospace engineering. the Ohio State.

“With this software, it is not difficult to create robots or other devices with over 20 components that are much easier to control. It is a huge step in our ability to design nanodevices that can perform the complex actions we want them to do. . “

The software has a variety of benefits that will help scientists design better and more useful nanodevices and – the researchers hope – shorten the time before they are used every day.

One advantage is that it allows researchers to truly realize the entire design in 3-D. Earlier design tools allowed creation in 2-D only, forcing researchers to map their creations to 3-D. This meant that the designers could not make their devices too complex.

The software also allows designers to build “bottom-up” or “top-down” DNA structures.

In the “bottom-up” design, researchers take individual strands of DNA and decide how to organize them into the desired structure, which allows fine control over the structure and properties of local devices.

But they can also take a “top-down” approach, in which they decide how to model their overall device and then automate how the DNA strands are assembled.

The combination of the two allows to increase the complexity of the general geometry, while maintaining precise control over the individual properties of the components, Castro said.

Another key element of the software is that it allows the simulation of how the designed DNA devices would move and function in the real world.

“As you make these structures more complex, it’s difficult to predict exactly what they will look like and how they will behave,” Castro said.

“It’s essential to be able to simulate how our devices work. Otherwise, we’re wasting a lot of time.”

As a demonstration of software capability, co-author Anjelica Kucinic, a doctoral student in chemical and biomolecular engineering at Ohio State, led researchers in developing and characterizing many software-designed nanostructures.

Some of the devices they created included robotic arms with claws that can lift smaller objects and a hundred-nanometer structure that looks like an airplane (“The plane” is 1000 times smaller than the width of a human hair ).

The ability to make nanodevices more complex means they can do more useful things and even perform multiple tasks with a single device, Castro said.

For example, it is one thing to have a DNA robot that, after injection into the blood, can detect a certain pathogen.

“But a more complex device can not only detect that something bad is happening, but it can also react by releasing a drug or by capturing the pathogen,” he said.

“We want to be able to design robots that respond in a certain way to a stimulus or move in a certain way.”

Castro said he expects MagicDNA software to be used at universities and other research labs in the next few years. But its use could expand in the future.

“There is a growing commercial interest in DNA nanotechnology,” he said. “I think in the next five to 10 years we will start seeing commercial applications of DNA nanodevices and we are optimistic that this software can help stimulate this.”