Bar codes are everywhere. They're on cereal boxes, paint cans, and even lipsitck. If some researchers have their way, the microscopic equivalent of bar codes could infiltrate the molecular world just as widely.
By labeling molecules, the new bar codes could prove valuable for diagnosing diseases and tracking the success of treatments, says Michael J. Natan of SurroMed in Mountain View, Calif. He and his colleagues from SurroMed and Pennsylvania State University in State College report on the new tags in the Oct. 5 Science.
Nanoscale bar codes could also be applied far beyond biomedicine, suggests L. Andrew Lyon of the Georgia Institute of Technology in Atlanta. For instance, they could make it possible to unobtrusively ide