Fig. 2.

Sensitivity of the developed MPI brain scanner. 50 μl samples of Perimag with varying dilutions are moved to three positions on the FOV diagonal (upper 6 images). The sample is considered to be detected if the movement of the sample correlates to the signal shift in the image. Below 2 μg_Fe this correlation fails. The same procedure is done with an ellipsoid of 134 ml filled with different concentrations (lower 3 images). At a concentration of 14.7 ng_Fe ml⁻¹ (263 pmol _Fe ml⁻¹, 2 μg_Fe total) the position is still detectable while it fails at concentrations below that value