An image from an article published today in Nature showcases seemingly simple designs meticulously carved from DNA canvasses. As described in accompanying Nature News piece, the study by Bryan Wei, PhD, Peng Yin, PhD, and colleagues at Harvard University created finite yet complex figures from unique 42-letter, single strands of DNA that fold to form rectangular tiles.
Ed Yong writes:
In their simplest configuration, the tiles produce a solid 64-by-103-nanometre rectangle, but Wei and his team can create more complex shapes by leaving out specific tiles. Using this strategy, they created 107 two-dimensional shapes, including letters, numbers, Chinese characters, geometric shapes and symbols. They also produced tubes and rectangles of different sizes, including one consisting of more than 1,000 tiles.
The team designed a robot to pick the tiles. The desired shape is drawn using a graphical interface, and the robot picks out and mixes the required strands. It can produce 48 shapes in as many hours.
Yin says that “any technological applications are highly speculative”. But he thinks he could create DNA tiles using L-DNA, a mirror-image form of the classic double helix that is not found in nature. Such structures might be useful for designing nano-scale devices for delivering drugs, especially because they would be less likely to be broken down by DNA-cutting enzymes or trigger an immune reaction.
Yong contextualizes today's findings by noting that the Harvard scientists' work follows three-dimensional figures designed by DNA nanotechnology pioneer Ned Seeman, PhD, in 1991, and DNA origami methods introduced by Paul Rothemund, PhD, in 2006.