Active control of dynamic supraparticle structures in microchannels

Paramagnetic particles in microchannels form dynamic and reversible self-assembled regularly spaced structures when exposed to an external magnetic field. The magnetically induced micron-scale patterns can be formed and reformed spontaneously, thus providing an alternative to traditional microfabrication techniques for pattern creation. Under the influence of a varying magnetic field, these structures could be rotated through all axes without loss of structural form allowing dynamic micron-scale movement without direct mechanical, electrical, or photonic interactions. The structures are not attached to the wall of the enclosure and are free to move without loss of form from both pressure-induced flow and electrokinetic effects. The dynamic supraparticle patterning can be used in an extensive variety of on-chip applications and for unique microfabrication techniques.