What's the sound of two molecules touching? Ask James La Clair and Michael Burkart, two University of California, San Diego, scientists, who recently developed a biosensor on the surface of an ordinary compact disc. Data from a CD is nothing more than a stream of 1s and 0s, the digital representation of how laser light reflects off the disc's aluminum platter. Any dust or scratch on the CD's surface produces errors in the playback; La Clair reasoned that biomolecules would do so as well.
After experimenting with music CDs, the team turned to data CDs. They assigned a string of bytes to represent each ligand (they used biotin and mannose), and then burned those bytes onto the disc. The data's geographical location guided an inkjet printer, which coated the disc's appropriate region with the molecules. The disc was then mixed with sample, washed, and played; errors in the data stream ...
