Danish researchers have made a nano-sized box out of DNA that can be locked or opened in response to 'keys' made from short strands of DNA. By changing the nature or number of these keys, it should be possible to use the boxes as sensors, drug delivery systems or even molecular computers.
Jørgen Kjems, Kurt Gothelf and colleagues from Aarhus University, Denmark, have taken an existing technique known as 'DNA origami' into a whole new dimension. The technique traditionally uses a few hundred short DNA strands to staple longer DNA strands together to create two-dimensional nanostructures, usually building from a solid surface that supports the structures.
'But in this case you have things standing up,' says Kjems. 'And this makes the structures more fragile and much harder to image, so just to prove that you actually have your structure can be quite difficult,' he adds.