The device might turn out to be a boon in many fields. It could be used to study how individual cells interact with other things in their environment, such as viruses. “I can make a spot so small that it can act as a piece of glue for a single virus particle, and the shape of the spot can be used to control its orientation,” Mirkin says. Viruses in a several different positions could then be exposed to individual cells, with thousands of identical experiments performed at the same time to get statistically significant results.
Researchers could also study the size and distribution of patches of proteins on a cell’s surface that are responsible for anchoring it in place, says Mrksich. This could help them understand how cancer cells detach from a tumor and spread throughout the body, which could suggest new cancer treatments. Stem cell research might also benefit, Mrksich says, since the tool would allow researchers to study how cell attachments can influence how stem cells specialize into particular types of mature cells.
The technology might also have applications outside the lab; for example, it could tag pharmaceuticals with invisible codes to help drug companies identify counterfeit pills, says Mrksich.
Although such a precise method of printing might seem like a good fit for the electronics industry as well, in the past, many have been skeptical about its use there because of the slow speed of dip-pen nanolithography with a single pen.
Calvin Quate, professor of electrical engineering at Stanford University, says the 55,000-pen array “would go a long way” to changing his mind. But he warns that Mirkin will face stiff competition. “The thing that startles me is optical lithography has made such huge progress” that even with the added speed, the resolution of the technique may need to improve before it could compete.
So, at least for now, the best bet for dip-pen nanolithography may be in creating miniscule patterns of molecules suited to revealing the most detailed workings of life.