Credit: Image courtesy of Yin Zhang.
A team of scientists has developed a method to create structures whose building blocks are a millionth of a meter in size by encoding DNA with assembly instructions. In a series of experiments, the researchers mixed four "flavors" of droplets (yellow, orange, green, and blue), each coated with different DNA, but which do not bind. They then added a new droplet (red), which specifically binds to the orange droplet and activates it for the next step in the assembly. This process spurs the creation of a droplet chain in a pre-determined order (red-orange-yellow-green-blue).