Via my friend Don Weber*, via Slashdot, via Science (the journal, and, I suppose, thence via science, the epistemological pursuit), comes a report from IBM Zurich on imaging single surface adsorbed molecules at the atomic level** using an AFM tip functionalized with carbon monoxide atoms. Imaging single adsorbed molecules, not in a lattice context, is very difficult. In this case, they were directly imaging Pauli repulsion, which is pretty neat. It's interesting to think, sometimes, that the fact that your coffee cup doesn't pass through the table is basically just the Pauli exclusion force at work. And here it is, again, writ very small. I don't know what the implications for biology are, since interesting biological molecules are generally not planar. But interesting work nonetheless. c.f. this work on imaging single spins using an AFM.
*Before I went to grad school, Don and I worked at a now defunct software company together in Chicago called Geodesic Systems, and shared an office with two other people. I once gave a lunchtime talk on biophysics, back when I had never given any talks and didn't really know how to give a decent talk, and Don fell asleep in the middle of the talk. His comment upon mailing this to me was, "I didn't even fall asleep while reading it!"
**More memories: We did an AFM lab when I was an undergrad, with a "teaching" AFM, trying to image a HOPG lattice. The AFM was suspended from the ceiling using bungee cords as a method of noise dampening. Unfortunately, in the other half of the lab, people were trying to do Compton scattering, which involved moving lead bricks around. We would sit, holding our breath, as line after line of the image would form, and then somebody on the other end of the lab would drop a lead brick on the ground: BANG! And the image would do the optical equivalent of a phonograph needle squealing on a record. Fun times, fun times.
Friday, August 28, 2009
Thursday, August 20, 2009
- Steve Quake sequences his own genome, one molecule at a time (Nature Biotechnology)
- SMB writes up the Aspen conference on SMB as a guest editor at Current Pharmaceutical Biotechnology, hosting a special issue on single molecule biophysics. Steve's essay is free, but the rest of the articles you have to pay for, I guess, or. At least, Stanford doesn't give me online access. (Your guess is as good as mine as to what any of this has to do with pharmaceuticals.)
Friday, August 14, 2009
My experiment may be made of fail, but at least there's funny stuff on the intargoogles to cheer me up, with the knowledge that there are some really dumb people out there. Some of my recent favorites:
Tuesday, August 4, 2009
Does anybody know if there's a DNA synthesis company that will make oligos modified with ATTO dyes? I've looked at IDT, Midland, and Sigma-Aldrich. I want to do a quick-and-dirty experiment which will be easier if I can just buy a pre-modified oligo, and if it works, I can then maybe buy amine-modified oligos and label my own.