Johns Hopkins engineers used Legos to model microfluidic arrays at more easily observable scale, reports Scientific Blogging. Researchers led by Joelle Frechette and German Drazer used small beads, a glycerol-filled tank, and Legos to see what happens on the micro- or nano-scale of a microfluidic array. "Our experiment shows that if you know one single parameter—a measure of the asymmetry in the motion of a particle around a single obstacle—you can predict the path that particles will follow in a microfluidic array at any forcing angle, simply by doing geometry," Drazer says. They report their results in Physical Review Letters.