Sunday, August 28, 2005

These 'bots are made for walkin'

dna1   dna2

Do you remember the "DNA walker" that made headlines last year? (Stories can be found here, here and here)

I hadn't gone through recent nanotech patents and applications in a while, so when I was browsing through them yesterday I was pleased that New York University chemist Nadrian Seeman and his colleague William Sherman had filed a patent application in June.

Seeman is one of the rare working, grant-getting, patent-producing nanoscientists who believes that nanotech will eventually progress beyond building better tennis rackets and create useful things from the bottom up -- at least, one of the few who can openly admit it without jeopardizing his ability to get government grants.

Just last June, Spencer Reiss of Technology Review asked Seeman whether nanomanufacturing was "imminent" and how he would respond to "nanotech's skeptics" (read "molecular manufacturing"). The professor did not take the bait and responded that it's not going to knit sweaters anytime soon, but:

    "Everything we're talking about is doable. Is it doable on a scale that's going to be worthwhile? No one knows. In 25 years we've taken something that was in my imagination to the point where we can take out patents and where there are now whole conferences devoted to the topic."
And of course his patent application is winding its way through the system now.

I'll lay aside the question of molecular manufacturing for now, since that often turns too emotional and unproductive. However, even other scientists who don't really care whether nanobots will someday knit a sweater or cure world poverty can look at Seeman's DNA walker and see what's there for them.

The walker was made of fragments of DNA that strolled on two legs just 10 nanometers long. The little beast took two steps forward and two back.

Obviously, there isn't much use for DNA walking around. But it served its purpose -- it made headlines and drew attention to his research. Seeman acknowledged that the DNA walker is not going to be next holiday season's must-have toy. The point, he said, is to design molecules and get them to assemble into specific three-dimensional structures. In Seeman's mind, that could lead to some kind of nanomanufacturing application much like a Detroit-style assembly line, but with DNA robots pushing it down the track.

Now, here's where the process gets tricky and can break down. As I've written before, these basic researchers do not necessarily know what exactly it is that they have. That's where entrepreneurs or other specialists can come in. You don't like molecular assemblers or think they're impossible, or too long-term? Well, don't use it for that. I don't know. Maybe you have no use for walking DNA robots at all. However, they also link together into scaffolds, which might be of more use in assembly of nanoparticles of the type you desire. DNA was born for self-assembly. So, if you could get DNA to bend to your will by programming it to assemble into any structure you want, what would you do?

Oh, one more thing about that patent application. I had not known that the research was funded, in part, by the Office of Naval Research and the U.S. Air Force. Hmmm. I don't know about you, but I'm thinking that both branches are planning on some pretty fantastic voyages.

Further Reading
Not Your Daddy's DNA
Smallest Robot (with a video link)

No comments: