Light microscopy and magnetic resonance characterization of a DMSA-coated magnetic fluid in mice

Light microscopy and magnetic resonance were used to investigate the biodistribution of magnetite nanoparticles coated with dimercaptosuccinic acid, after intravenous injection of a single dose in mice. Morphological analysis showed a huge amount of magnetic nanoparticles (MNPs) in the lung 30 min after injection. In contrast to the lung, morphological analysis revealed lower concentration of MNPs in the liver. A progressive decrease of MNPs in both lung and liver was observed from 30 min to 4 hours after intravenous injection. MNPs were not observed in any other organs using morphological analysis. In support of the LM observations MR signals were detected in both lung and liver as early as 5 min after injection. In addition, no MR signal was observed in the blood stream as early as 5 min after injection of the single dose.