Self-assembling colloids to advance capabilities of nano-fabrication 10/22/2013 - 00:00 Scientists in the US have devised a stunningly simple way to direct colloids to self-assemble in an almost infinite variety of configurations, in both two and three dimensions. The technique, which relies on the creation of a pre-determined pattern of magnetic fields to generate a ‘virtual mould’ to dictate the final position of the particles, can be used to separate and distribute, in a controlled way, anything from living cells to ions.