A magnetic force driven chaotic micro-mixer

A magnetic force based chaotic micro-mixer is developed for mixing of magnetic beads in bio-fluids. The mixer consists of micro-conductors embedded in the substrate and micro-channel on top. We have shown that the magnetic field generated by the simple 2-D micro-conductors provides strong attraction to the nearby magnetic beads. Numerical simulation was used to search for the chaotic regime of particle trajectories. It is found that the serpentine channel geometry with the perpendicular electrodes arrangement is able to create the stretching and folding of material lines, which is a sign of chaos. The existence of chaos is also verified by using the dynamical tools, such as Lyapunov exponent and Poincare map.