Friday, January 4, 2008

Zapping Cancer

I talked a bit about the technology before, and today I have discovered that the situation is actually somewhat more complicated than I had thought. (That's how scientists admit to being wrong.) The full Nature article is here. And an additional excerpt:

The work is intriguing, says Hongjie Dai, from Stanford University in Palo Alto, California, who is using near-infrared radiation with nanotubes in similar systems in mice. “If indeed effective, it would be more desirable than the near-infrared laser heating method,” he says.

But Dai says that the reasons why the nanotubes get so hot need more investigation before the system can be advanced. “The physics behind the radio-frequency heating is not clear,” he says.

In test experiments, a suspension of nanotubes in water got as hot as 45ÂșC within 25 seconds when treated with radiofrequency waves. “I was really amazed by the amount of heat that was released by these nanoparticles,” says Curley.

He attributes the phenomenon to the “unique electronic properties” of carbon nanotubes. It might also be that the tubes align themselves into antennae-shaped arrangements to conduct heat better. Curley says that he has as-yet-unpublished evidence to better explain his findings.

Part of the remaining challenge is to remove the two to three millimetre “zone of damage” around the nanotube-containing cells, he says.

And the intention is to one day create nanoparticles that seek out cancerous cells, rather than having to inject them into tumours. This would be done by sticking targeting molecules on the outside of the tubes: antibodies or proteins designed to recognize a site on a cell that is cancerous, says Curly. This would mean that nanoparticles could infiltrate cancer cells selectively, before the radio waves are applied. The team is working on this.

The Onion weighs in.