The relentless pursuit of smaller components for everything from electronics to medical devices is making nanotechnology increasingly attractive to manufacturers. But one of the biggest challenges in the field is finding a cheap, easy, and fast method for building things on an extremely small scale.

One possible solution is dip-pen nanolithography, which a Northwestern University startup called NanoInk is commercializing. The technology, pioneered in 1999 by Chad Mirkin, a chemistry professor at Northwestern and NanoInk's founder, uses microscopic tips coated with a material that is deposited as "ink" on a surface. The approach makes it possible to "write" with a wide range of inks-metals, DNA, proteins-on an equally wide range of surfaces, such as silicon, glass, or metal. "We have total flexibility of inks and surfaces, which makes dip-pen nanolithography very attractive," says Cedric Loiret-Bernal, the company's president and CEO.