In the last ten years, I think big progress has been made in understanding lots of little machines in living matter. They’re mechanisms inside the body. First, by controlling the genes, you can produce these little machines in large quantities. Or by suppressing little bits in the genetic sequences, you are able to remove some parts of the program and see if it still operates. The genetic side of this research helps build understanding of the machinery that produces this system. Second, lots of physicists have started making these smaller and smaller experimental devices by which you can handle a single molecule at a time. So instead of looking at a whole cell with everything functioning in parallel (which blurs the picture of the operation of individual elements), you can start to study molecules one by one. Then you can test them in circumstances that would resemble their functioning in real life.

—Armand Ajdari of the Laboratoire de Physico-Chimie Thèorique in Paris, France, speaking at the Department of Physics’ conference on nanobiology on October 26, 2001.