Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Materials

DNA In Another Dimension

3-D construction technique creates a wealth of structures

by Bethany Halford
May 25, 2009 | A version of this story appeared in Volume 87, Issue 21

[+]Enlarge
Credit: Shawn Douglas
Models of 3-D nanostructures made from DNA.
Credit: Shawn Douglas
Models of 3-D nanostructures made from DNA.

USING DNA as a basic chemical building block rather than a genetic molecule, scientists have devised a method for creating complex three-dimensional nanostructures with precisely controlled dimensions that range from 10 to 100 nm (Nature 2009, 459, 414). The strategy of self-assembly could provide a general route for manufacturing sophisticated devices with nanoscale features, the researchers say.

The technique, developed by William M. Shih of Boston's Dana-Farber Cancer Institute and colleagues, is an extension of DNA origami, in which hundreds of short oligonucleotides fasten to a long single strand of DNA in such a way that it folds into a predetermined shape (C&EN, March 20, 2006, page 10). Researchers have already used the technique to create 2-D snowflakes and smiley faces, as well as a 3-D DNA box (C&EN, May 11, page 30). Shih's strategy allows nanotechnologists to build a vast diversity of 3-D DNA structures, a capability his group demonstrated by constructing a tiny railed bridge, a genie bottle, and an icosahedron.

Shih's team designs the structures by computationally "carving" them out of a honeycomb lattice made of a DNA double helix. Using computer-aided design, they arrange a single strand of DNA so that it winds around that carved structure and then determine what short oligonucleotides are required to hold it in place.

"The challenge was actually getting it to work," Shih tells C&EN, because DNA is negatively charged, and repulsive forces tend to keep it from packing into the compact sculptures. "We didn't know what kind of tricks we would need to get it to fold correctly," he says. Ultimately, patience proved to be one of the tricks. Although most 2-D DNA origami structures fold within an hour, Shih's 3-D sculptures take about a week to fold.

"This successful move into three dimensions heralds a new era for the field of structural DNA technology," writes Duke University chemistry professor Thomas H. LaBean in a commentary that accompanies the paper. "Through the ages, some of the most iconic and lasting artifacts of human ingenuity have been sculptures and carvings, created from a wide variety of materials. But until now, a general purpose material from which nanometer-scale, three-dimensional shapes could be made has been lacking."

Advertisement

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.