Derek Hansford’s unobtrusive bearing is just what you’d expect from someone who designs ways to sneak drugs past the immune system. Hansford has been fabricating tiny polymer particles that can hold drugs and be injected into a patient’s bloodstream. Once there, they could hunt down tumors and release their drugs, without affecting healthy cells. Along the way, the particles would shield the drugs from degrading enzymes and would not elicit attacks from the immune system—a common problem for cancer drugs—because they do not attract immune cells. Although other bioengineers are making polymer drug-delivery devices, none has made large numbers of uniform particles small enough to travel in the blood-stream; each of Hansford’s particles is about the size of a red blood cell. The scientist has adapted a technique called soft lithography to make the particles, casting hundreds of millions of them in varied shapes out of reusable molds. Startup company iMedd plans to license his technology. Hansford will now try to make particles for inhalable drugs—an alternative to injections.