Static particle separation utilizing cascaded magnetic fields

If a sample of magnetic nanoparticles (MNP) contains two groups of different mean size, (as is the case for, e.g., Resovist
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[1]), bimodal fit from M(H) measurement data may reveal the bimodality. However this estimation may fail if the mean particle size of the two groups is too similar. Here we suggest magnetic separation as a useful tool for analyzing such MNP samples. To this end, we have implemented the static magnetic separation with a commercial soft magnetic spheres filled column (Miltenyi) in cascaded runs at different field strengths.