New software creates 3D nanostructures out of DNA to create miniature containers for delivering drugs

Science and Technology Daily Beijing, Dec.
27 (Reporter Zhang Mengran) According to the latest issue of Science Advances magazine, a new open-source software program developed by researchers at Duke University and Arizona State University in the United States allows users to draw circular drawings or digital models and convert them into 3D structures made of DNA, each of which is a tiny hollow body with a diameter of no more than five millionths of a centimeter, and a needle can hold more than 50,000 such microstructures
.

The researchers say these are not just nanosculptures
.
The software allows researchers to make tiny containers to transport drugs, or molds for casting metal nanoparticles with specific shapes for solar cells, medical imaging, and more
.

For most people, DNA is the blueprint for life, the genetic instruction
of all living things.
But for new research, DNA is not just a carrier of genetic information; it is also source code and building material
.

There are four "letters" or bases in DNA's genetic code, which pair in a predictable way in the cell, forming the rungs
of the DNA ladder.
The researchers took these strict base-pairing properties of DNA—A and T, C and G—and by designing DNA strands with specific sequences, they could "program" them to piece them together into different shapes
.

The method involves folding one or several single-stranded strands of DNA thousands of bases long with the help of hundreds of short DNA strands that bind to complementary sequences on the long strands and "fix" them in place
.

The researchers developed the software DNAxiS, which works by coiling a long DNA double helix into concentric rings that are stacked on top of each other to form the outline of an object, much like
using clay rings to make a pot.
To make the structure stronger, the team can also reinforce them with additional layers to improve stability
.

The research team showed the various shapes they could make: conical, gourd, clover
.
DNAxiS, the first software tool that allows users to automatically design such shapes, uses algorithms to determine where to place short DNA "staples" to join long DNA loops together and hold the shapes in place
.

For example, given a mushroom-shaped model, the computer spits out a series of DNA strands that self-assemble into the correct structure
.
Once the strands are synthesized and mixed in the tube, the rest is processed on its own: by heating and cooling the DNA mixture, it magically folds into DNA nanostructures
in just 12 hours.

The researchers say their DNA design software is a big step
forward in automating the design of new three-dimensional structures.

Editor-in-Chief Circle

DNA, the biological macromolecule we are most familiar with, not only carries a lot of biological information, but now it can also be used as an important component of nanostructures and nanodevices - which is also a new hot spot
around DNA research in recent years.
DNA becomes a self-assembling material that can be folded like paper to build the desired 3D nanostructures
.
This article introduces a newly developed open-source software program that allows users to design various shapes by themselves, such as mushroom shapes, gourd shapes
.
At this moment, the software becomes a "magic pen Ma Liang", turning design drawings into construction drawings to help build DNA
.
In this way, the barrier to entry for creating 3D nanostructures with DNA can also be greatly reduced
.