DNA Origami and Nanoscale Folding

In 2006, the California Institute of Technology, working with IBM's Almaden Research Center, announced in the journal Nature Nanotechnology that it developed a way to create shapes and patterns using DNA. Essentially, developing a technique that has come to be known as “DNA origami.”

The DNA origami self assemble into a variety of different designs onto surfaces that work with semiconductor equipment. Each DNA structure is one one-thousandth the size of a human hair, allowing the final assembled piece to possibly be used as a miniature circuit board. This will allow for better assembly of computer chip components that will be cheaper to produce and more efficient than they are today.

click to enlarge

Also known as nanoscale folding, DNA origami research was created by the senior research associate of Caltech, Paul W.K. Rothemund and his team. He found that DNA molecules could react between one long strand of viral DNA and a combination of various shorter synthetic DNA strands. The short DNA strands will control the folding of the long strand, allowing the segments to become folded into a variety of two-dimensional shapes. This is accomplished using the concept of complementary base-pair binding. This creates a variety of different shapes as basic as a square or complex as a smiley-face. The entire process is conducted within a solution of saltwater.

One major challenge with making DNA origami research functional is to make sure the DNA attaches to the surface in a pattern in which the designers wish. This is accomplished by etching negatively-charged patterns into silicon wafers using electron-beam lithography and oxygen plasma. This causes the negatively-charged DNA structures to bind to the locations pre-determined by researchers by adding positively-charged magnesium ions to the saltwater.

click to enlarge

The process of nanoscale folding has a number of ramifications not just for computer technology, but also for biology and even art. The miniature circuit boards created through the process are useful in creating nanotubes and nanowires, but could also be useful for developing small nanotechnology machines that may be able to be grafted on to human tissue such as muscles. Potentially, DNA origami boards could be placed in a person's heart tissue to help control heartbeats. DNA origami has also been utilized in a small way to produce tiny versions of artistic expression. Besides Rothemund's famous smiling face, Brigham Young University created a miniaturized “BYU” logo in 2009.

Folding DNA to create nanoscale shapes and patterns

DNA Origami Representation. (Supplied by Tim Vickers at Wikimedia Commons; GNU Free Documentation License; http://upload.wikimedia.org/wikipedia/commons/9/9b/Holliday_Junction_cropped.png)

Circuit Board. (Supplied by Mike 1024 at Wikimedia Commons; Public Domain; http://upload.wikimedia.org/wikipedia/commons/6/67/PCB_design_and_realisation_smt_and_through_hole.png)