High R1 of Mn2+ Adsorbed to Hydrophilic Pores of Magnetoferritin Nanoparticles

Veronica Clavijo Jordan¹, Kevin M. Bennett¹

The enhancement of R1 due to paramagnetic ions can be modulated by controlling the sequestration and exchange of water protons around the ion. Here we report a new synthesis technique to enhance R1 by strategic placement of manganese (II) ions on the surface hydrophilic channels of apoferritin, causing a strong increase in R1. The results indicate that these manganese ions, when clustered in such channels on a highly filled apoferritin cavity (magnetoferritin), can create a per-ion R1 of 330mM-1s-1.