Gold standard: EPFL targets precise assembly of nanoparticles

Researchers in EPFL's Laboratory of Microsystems have found a way to precisely position hundreds of thousands of nanoparticles on a one centimetre square surface. According to EPFL, the nanoparticles were placed within one nanometre - versus 10 to 20 nanometres using conventional methods - and oriented within one degree.

Led by Jürgen Brugger, their work, which was published in Nature Nanotechnology, sets the stage for the development of nanometric devices including optical detection equipment and biological sensors.

"If we manage to place gold nanoparticles one nanometre apart, we could, for example, confine light to an extraordinary degree and detect or interact with individual molecules," said Valentin Flauraud, the lead author.

For their study, the researchers used gold nanoparticles that were grown chemically in a liquid.

"These nanoparticles exhibit better properties than those produced through evaporation or etching, but it is more difficult to manipulate them, because they are suspended in a liquid," said Flauraud.