SSS 2011-09-21

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Asbestos increases the risk for certain cancers. The fibers¹ are thought to do so by skewering² cells, setting off chemical reactions that lead to inflammation, DNA³ damage and cell death. Some studies have suggested carbon nanotubes might have similar effects—because they're long and spiky⁴, like asbestos. But why would a cell draw in a nanotube, essentially⁵ impaling⁶ itself on a microscopic⁷ lance?

 

To find out, researchers exposed mouse and human cells to carbon nanotubes. They saw that the cells frequently engulfed⁸ the tubes—almost always tip-first. They then simulated that sword-swallowing maneuver⁹ on a computer. And they concluded that the round tips of nanotubes feel like bite-sized spheres, which cells commonly ingest. But once the cell senses the nanotube isn't bite-size? It's too late. It can't stop sucking it in. The finding is in the journal Nature Nanotechnology.

 

As nanotubes may have medical applications, making them safe is key. And there may be a way to keep cells from biting off more than they can swallow—snip off the nanotubes' rounded tips. In one such simulation, the cells left the tubes alone—meaning we may get to have our nanotubes, without eating them, too.

 

Thanks for the minute. For Scientific American's 60-Second Science, I'm Christopher Intagliata.

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