For Stephanie Valentin, an artist at Sydney's College of Fine Arts, it was a new world to explore. Paul Munroe, a materials scientist at the University of New South Wales in Sydney, found it a rare opportunity to apply a tool commonly used for studying electronic circuits to a biological specimen. The result — a series of micrometre-high words carved into grains of pollen — went on display in Sydney's Stills Gallery on 11 September.
Valentin approached Munroe in her quest to find a method for writing on pollen. He suggested using a focused ion beam miller: a device usually used to etch the surface of electronic circuits. With Munroe's help, Valentin used a narrow beam of gallium ions to carve words on pollen grains with a diameter of around 20 micrometres.
The project has useful scientific spin-offs, as other researchers are interested in using focused ion beam millers to study biological samples. “What is notable is that they were able to use it to etch pollen without destroying it in the process, and with a very high degree of precision and control,” says Ian Williams of the Australian National University (ANU) in Canberra, who uses ion beams to analyse geological samples.
“Not much work has been done on biological materials,” says Sally Stowe, also at ANU. Stowe plans to use focused ion beams to scrutinize the interface between hard and soft materials, such as titanium implants in bone. The ion beam should allow her to carefully cut away layers of the sample without damaging it. “It's a nanoscale Swiss Army knife,” she says.