The SEM hosted the procedure, allowing the scientists to see the manipulation live. We can study the tubes in isolation, measuring them electrically, stretching them, kinking them, even breaking them. The data we can obtain is impressive, and there's immediate feedback. Invention is not unusual in Ruoff's lab. The technique uses photolithography to create patterns on a conductive silicon wafer surface.
Researchers then electroplate gold and cobalt metal to fill the holes in the pattern.
Removing the pattern leaves the particles, which can be scraped off the surface using a razor blade. Eventually, such directed design of identical nanoscale building block units may play an important role in nanoconstruction projects. But today, Ruoff's designer particles are piquing the interest of biologists, particularly David Ho, Ph.D., a professor of biology in Arts and Sciences, and plant researchers at DuPont. They are using the particles in biolistics, a procedure that introduces new genetic material into living cells by shooting them with DNA-coated microprojectiles. While biolistics is a common technique in plant transformation studies, variables relating mainly to the types of projectiles used have stymied scientists seeking to optimize the procedure.