Anita Goel, 32

Physicist and physician Anita Goel finds inspiration in the tiny: the proteins that inch their way along DNA, reading and copying the genes inside every cell. As a physics graduate student at Harvard University, Goel developed a theory to explain how these molecular motors work. While working on her medical degree at Harvard in 2004, she founded Nanobiosym to apply her theories to the development of nanotech devices for precisely controlling these proteins; such devices could identify viruses and bacteria in, say, a blood sample more rapidly, accurately, and cheaply than current techniques can. Her goal: a low-cost, handheld device for biodefense and biomedical applications.