So far, they’ve used this technique only to form pairs of pyramids. But they say it should be possible to hook many more together. By varying the sequences used and where they’re placed in the pyramids, such as at the edges or the points, the researchers say their pyramids could self-assemble into a variety of shapes. They hope DNA can readily serve as a scaffold for arranging other materials.
“It’s a great way of laying out an architecture with essentially atomic precision,” says Turberfield, “but to make some sort of useful molecular device, you’re almost certainly going to want to link other things, for example, molecular electronic components, to scaffolding like this to make a complete device.” Such components could include nanowires, which could lead to three-dimensional circuitry, perhaps for dense and powerful computers. They might also incorporate biological molecules for sensing or fluorescing chemicals for imaging applications.
The biggest advantage of these pyramids may actually be their initial lack of complexity. Patrick Doyle, an MIT chemical engineering professor who studies the dynamics of DNA, says the design is “rather elegant.”
In the past, three-dimensional DNA structures were built with a painstaking series of steps, and ultimately produced few copies. These pyramids, however, which are formed with the aid of heating, then cooling the DNA strands, take only one step to assemble and produce much higher yields.
“One of the virtues of this structure is the extreme simplicity and very high yield and speed of synthesis,” says Turberfield. “If you want a building block to make lots of other things with, you don’t want to be toiling over the construction of the building block – you want that to be easy. Then you can go on to do the harder stuff, by linking it later.”