ASU team offers precise DNA origami technique with novel shapes and delivery potential

Multiple shapes demonstrated using DNA origami--Courtesy of ASU

Folding DNA into new, functional shapes isn't a new technique, but researchers at Arizona State University have demonstrated novel design methods that allow them an amount of control over the genetic substance never seen before, creating new three-dimensional shapes that could ultimately be used in drug delivery.

Hao Yan of the university's Biodesign Institute at the Center for Molecular Design and Biomimetics used wireframe designs--simple sketches of 3-D objects--that can be used to create actual DNA shapes that include spheres, spirals, flasks, Möbius forms and, according to the university, a robot shaped like a spider that can "walk" along a DNA track. The technique has been called "DNA origami."

To build them, the researchers capitalized on the fact that DNA is made up of only four simple nucleotides that self-assemble according to specific "rules." By putting them together in prescribed ways, many different shapes can be constructed.

Using the simple building blocks of DNA, these objects can be programmed to hold drugs and release them at a given point--they also have the potential to create complex DNA robots with precise controls. Most of all, the work shows that scientists can control DNA shapes in unprecedented ways, revealing almost unlimited capacity to develop nano-sized objects capable of drug delivery, among many other functions.

The team published its findings in the journal Nature Nanotechnology.

"Earlier design methods used strategies including parallel arrangement of DNA helices to approximate arbitrary shapes, but precise fine-tuning of DNA wireframe architectures that connect vertices in 3D space has required a new approach," Yan said in a statement.

The new technique allows the scientists to vary the vertices between lines of DNA from two to 10 arms emanating from each vertex. This gives each shape an immense number of possibilities.

- here's the report from ASU
- and here's the abstract