Optimization Design Of The Configuration Of The Microchannel Of The Lab-on-a-chip For Magnetophoresis Cell Sorting

Magnetophoresis has been widely used in separation of bio-samples represented by cells from their background media, where magnetic beads are normally used as the carriers with bio-samples specifically or nonspecifically attached to them. Based on related theories of General Mechanics, Fluid Mechanics and Electromagnetics (mainly involve three groups of equations describing motion, magnetic field and flow field successively), the present paper studies the forces acting on the spherical magnetic solid particle (magnetic bead) under the effects of flow field and magnetic field. Using the related software, through numerical simulation, the physical model of magnetophoresis cell sorting unit has been set up. The model includes the permanent magnet, the flow, magnetic beads and a microchip which is consist of one main channel, two subchannels and the wall. The physical and geometric parameters which influence the magnetic beads` trajectory has been analysed. It is found that the magnetic beads is highly sensitive to their positions, only the particles can enter the subchannels successfully and avoid the common blocking in the vicinity of the subchannels, which are released in a specific zone and move in an appropriate zone. While the magnetic beads` positions are determined by the configuration of the microchannel to a great extent. Then the optimization design of the configuration of the microchannel has been conducted accordingly. Finally, the continuous sorting of multi-sized magnetic beads has been accomplished simultaneously (to realize the continuous sorting of cells).