Scientists have developed a way of trapping single sperm cells inside metal nanotubes. The direction of these 'spermbots' can be controlled remotely to deliver drugs or fertilize an egg.

The video below captures magnetic nanotubes 50 microns long by 5 to 8 microns in diameter that were dropped into a fluid containing bull sperm.

Watch here:

You can read the paper outlining this research here

What's the Big Idea?

"If I were to say someday you’ll have millions or even billions of nanobots, blood cell size devices going through your body and keeping you healthy from inside, I might think well, that sounds awfully futuristic."

The futurist and inventor Ray Kurzweil told Big Think this in TK before pointing out that early experiments were already showing promise, such as a blood cell-size device "that can detect and destroy cancer cells in the bloodstream."  

Watch the video here: