Diamagnetic Levitation of Beads and Cells Above Permanent Magnets

We show here that diamagnetic beads and living cells can be trapped using magnetic fields and gradients produced by structures of permanent magnets. First, four different techniques to fabricate levitation-compatible magnet configurations in both millimeter and micrometer scales are described. Then, the magnet structures are applied to levitate diamagnetic bodies in air and/or paramagnetic buffered liquids. This technique allows contactless manipulation of the particles, avoiding the risk of adhesion and contamination which might appear using classical handling technologies such as channel-based microfluidics.