The achievement, published in the September issue of Nature Nanotechnolgy offers a promising tool for use in a range of fields such as biomedicine, electronics and optical technologies.

In contrast to existing printing technologies, the new technique makes use of a self-assembly process that controls the arrangement of nanoparticles on the printing plate or template. "In traditional gravure printing, ink is scraped into the recessed features of a printing plate in which pigment particles are randomly dispersed", explained Tobias Kraus of the nanopatterning team in Zurich. "In our method, a directed self-assembly process controls the arrangement of nanoparticles."

The entire assembly is then printed onto a target surface, whereby the particle positions are precisely retained at a very high resolution. The researchers were able to print particles as small as 60 nanometers and position them very exactly and in a reproducible way. The printing template geometries explored include lines to produce closely-packed nanowires which could be used in molecular electronics, the researchers said. According to the group, the long-range accuracy of the method is similar to that of microcontact printing methods.

In one experiment, the researchers achieved the controlled placement of catalytic seed particles for growing semiconducting nanowires using a CVD process. Nanowires are said to be promising candidates for building post-CMOS nanotransistors.

Besides electronics, the process could be used to produce arrays of biofunctional beads that can identify certain cells or markers in the body, for instance in cancer tests or to detect heart attack markers.

Since nanoparticles also interact with light, the technology also could be used in optoelectronic devices, using creating optical materials with new properties - if the printed structures are as small as the wavelength of the light, they could form lenses that band light inside future optical chips, the researchers raved.

For optical and biotechnological applications the method is relatively mature, researcher Heiko Wolf explained. For electronics applications however, the long range accuracy has yet to be optimized before industrial solutions would be realistic, he said.