By tinkering with the four base sequences in DNA, scientists can manipulate pieces of DNA to attract other pieces and begin to assemble a kind of DNA machine.
But for a machine to work, it needs to have both mobile and stationary parts and that's what Seeman and Ding have done.
The researchers built a two-dimensional scaffolding of DNA and then inserted a component that contained an arm also made of DNA.
The "shoulder," or the place where the arm connected to the component contains a particular sequence of DNA. With this sequence, the arm pointed up. When the researchers changed the sequence, the arm pointed down.
"This is the first work to show that you can incorporate mobile parts into a 2-D arrangement of DNA," said Chengde Mao, assistant professor at Purdue University in West Lafayette, IN.
The next step, says Seeman, is to incorporate more arms in the robot and manipulate each of them in a slightly different way at the same time.
