In the future, troops of tiny medical devices might be dispatched into our bodies to take down diseases. Now, researchers are saying that they've found a new technique to design and 3D print nanoscale DNA that might one day help with drug delivery.
In a study published today in the journal Nature, researchers describe how they applied 3D computer-aided design techniques to fold complex DNA structures, then 3D print them at the nanoscale (a nanometer is a billionth of a meter). In contrast to conventional DNA origami methods (folding DNA strands into small two- and three-dimensional shapes) that produce more rigid, brick-like structures, the researchers have so far created rounder, flexible shapes: everything from miniscule human-like figurines to rabbits, bottles and balls.
"What we've been trying to do here is create a technology that would allow a user to sit down at a computer and draw a 3D model, then print it out afterwards," explained Björn Högberg, corresponding author of the study and an associate professor at the Karolinksa Institute in Sweden, over the phone.
"This method is different because it allows us to create structures that are much more complex than were previously possible. You can mimic the polygonal meshes that are so integral to digital 3D design," said Högberg.
The researchers first use their software to design their shape, then use algorithms to turn their polygonal mesh shapes into a design that can be rendered by DNA. "It lowers the learning curve," said Högberg, noting how it made 3D DNA design easier for doctors and scientists.
As this new technique creates shapes that are rounder and more flexible, Högberg said, it opened up applications in drug delivery and phototonic devices (components for detecting light) in the future.
"When we create these structures this way it turns out they are much easier to fold in the salt concentrations that we normally have in our bodies," explained Högberg.
According to Högberg, traditional DNA origami models require more magnesium, which is found at very low concentrations in the body. Adding salt, however, is thought to make the DNA structures dissolve, said Högberg.
"It's possible that these structures can withstand a biological environment that closely resembles the human body. This might be advantageous for drug delivery applications," he added.
While the shapes you can make with the team's software seem pretty limitless, Högberg added that if you want to see your design in physical form, you'll still have to send it off to a DNA synthesis company, then peer through an electron microscope to actually see it. So for the moment, these miniscule creations are best enjoyed in digital form.