Levitation and position of T47D cells on a magnetic microsystem fabricated by ink jet printing

We present the levitation and residing at particular places of human breast cancer (T47D) cells on a magnetic microsystem quickly fabricated by printing. The microsystem consists of arrays of soft magnetic elements and is put adjacent to a bulk magnet. Under a magnetic field generated by the magnet, elements are magnetized, obtaining a significant magnetic field strength and a high magnetic field gradient in the micro-space above them. The field applies a magnetic force on the cells as they are dropped to the surfaces of the elements. As a result, levitation and a stable position for each cell are observed. The levitation and position of a cell can be predicted by a theory that takes into account the magnetic, buoyant, and gravitational forces on the cells. Our theoretical and experimental results agree well with one another, and the microsystem is capable of efficient cell manipulation.