According to Science Daily, a team of interdisciplinary scientists from Columbia University, Arizona State University, the University of Michigan, and the California Institute of Technology have invented what may sound like an arachnophobe's worst nightmare: nanoscale robotic "spiders" small enough to crawl around on your DNA.
Despite sounding like the plot for a B-grade sci-fi horror flick, the scientists promise that their creation will be a boon for medical science, and in a smorgasbord of ways.
"The idea is to have molecular robots build a structure or repair damaged tissues," said Milan N. Stojanovic, who led the project.
"You could imagine the spider carrying a drug and bonding to a two-dimensional surface like a cell membrane, finding the receptors and, depending on the local environment, triggering the activation of this drug," added Hao Yan, one of the project's key researchers.
The molecule-sized robots are small enough to crawl around on your DNA, and they're actually made from DNA, too. And although they aren't the first nanobots made from DNA (Stojanovic himself invented DNA spiders several years ago), these latest upgrades on the design are remarkably more advanced. Previous spiders could walk no more than three steps. "This one," said Yan, "can walk up to about 100 nanometers. That's roughly 50 steps."
But perhaps even more impressive than getting them to walk greater distances, scientists were about to create spiders that can follow complex commands. Unlike in normal macroscale robotics, molecule-sized robots are too small to store information. A fundamental dilemma within nanorobotics, therefore, is how to program bots to follow instructions.
The research team had a novel solution: "The idea instead is to store information on the commands on the outside," said Nils G. Walter, a chemist on the team. And you do that, added Stojanovic, "by imbuing the molecule's environment with informational cues."
And they did that with a technology called, interestingly enough, DNA origami. Much like the art of folding paper, DNA origami is the technical practice of folding structures of DNA. In this case, researchers exploited the shapes to create a custom-made track for the nanospiders to follow.
Despite the breakthroughs, researchers warn that a lot of work still needs to be done before the spiders can be put to practical use. It may take as long as 100 years before they meet their full potential, noted Stojanovic. So while the advances represent one giant leap for nanorobot kind, they represent — quite literally — only a few small nanometers for us.
"But," Walter adds, "just as researchers self-assemble today to solve a tough problem, molecular nanorobots may do so in the future."