These Microscopic Robots Will Swim Into Your Colon and Save Your Life

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Have you ever seen how doctors take samples from the colon for cancer screenings? They prod the organ with toothed forceps that should be relegated to a James Bond villain's torture tool set. But now, thanks to a team of researchers, medical professionals may soon be able to ditch the painful tools for starfish-like nanobots no bigger than the point of a pen.

David Gracias and his team from Johns Hopkins University created what are called microgrippers, which measure half a millimeter (about .02 inches). With star-like arms, they change their shape to react to body temperature, pH levels and enzymes, and grip the tissue they touch, performing a biopsy in the process.

Here's what that process looks like currently, without the tiny robots: 

Forceps in action. That's a colon.  IEEE Spectrum/YouTube

With Gracias' microgrippers, the process is much less invasive:

Nanobots shot into a colon.  IEEE Spectrum/YouTube
A nanobot at work.  IEEE Spectrum/YouTube

So far, the miniature biopsies have been performed on animals. These robots can be injected into the patient's colon with a tube, then, when the procedure is over, retrieved with a magnet or taken from the patient's stool. 

There are a few problems: According to estimates from the researchers, only one-third of the robots typically grabbed tissue. That sounds like poor odds, but if thousands of these nanobots are used at a time, the little swimmers could be extremely effective.

One early issue with nanobots is the risk of creating clots in the bloodstream when the 'bots are packed in tighter quarters. "When you talk to clinicians, one thing that makes them go white and never want to talk to you again is any kind of notion of putting something solid in the bloodstream," John Rogers, a researcher at the University of Illinois at Urbana-Champaign said, according to IEEE Spectrum. "There are just really serious consequences of any kind of structure that's free-floating and just traveling around."

Nanobots with a penny for scale.  IEEE Spectrum/YouTube

Right now, the colon is the easiest testing point: It's huge (by body standards) and naturally ushers objects and fluids through the body. Eventually, these nanobots could be used in more complicated human experiments, such as performing tasks on eyes, unclogging arteries or treating other cardiovascular issues. And more importantly, we could leave behind the invasive probes of today.