(In the 2006 paper, Rothemund famously used the technique to create miniature DNA smiley faces measuring 100 nanometers across and 2 nanometers thick). Researchers begin with a long strand of DNA ...

In 2006 Paul Rothemund of the California Institute of Technology 'folded' DNA to create two-dimensional shapes ranging from a basic rectangle to a personable smiley face (Rothemund, 2006).

Then, to confirm the structures, he used atomic force microscopy. With his new DNA folding method, Rothemund created smiley faces and other patterns, such as DNA lettering. At the time, Winfree ...