Tuesday, April 26, 2005

Diseases betrayed by cantilevers of love


If you're wondering whether nanotech will ever break into something more meaningful than a few novelty items like stain-proof pants and extra-bouncy balls, the more interesting products are on their way, with cancer in their crosshairs. The VeriScan Biosensor System from Protiveris caught my attention today because of the company's claim that its microscale cantilevers are somehow related to nanotech. A closer look tells me that, yes, Protiveris has every right to enjoy the prefix.

A cantilever is a tiny "diving board." For liberal arts folks, think Frank Lloyd Wright's Falling Water, stamp out any number of copies, line them up in arrays and then "microsize" them. Then, it's time to introduce the "live bait." Coat each cantilever on one side with a protein, antibody or even a snip of DNA, depending on what kind of prey you're after. Then step back and watch -- if you have really, really good eyes -- as complementary molecules just cannot resist the charms of their sexy soulmates all displayed like that on a diving board.

The poor suckers bind themselves to the board, the board bends and, bingo, you've got evidence that bad little things are carrying on inside your sample. Here's a flash animation of the process.

Where's the nano? Well, the cantilevers are bigger than nanosize, but the bending caused by the binding is measured by the nanometer.

So in other words, in this case anyway, it really is not the size that matters. It's all about the motion.

1 comment:

Daniel said...

Okay, I feel like I'm pimping the work of my group member, but you can also make the cantilevers nano - Nanobelts! See "Nanobelts as nanocantilevers", W. L. Hughes, and Z.L. Wang, Appl. Phys. Lett., 82 (2003) 2886-2888
Or on my group's website