Kinetics of elimination and distribution in blood and liver of biocompatible ferrofluids based on Fe_3O_4 nanoparticles: An EPR and XRF study

摘要

In this study, we evaluated the biodistribution and the elimination kinetics of a biocompatible magnetic fluid, Endorem~(TM), based on dextran-coated Fe_3O_4 nanoparticles endovenously injected into Winstar rats. The iron content in blood and liver samples was recorded using electron paramagnetic resonance (EPR) and X-ray fluorescence (XRF) techniques. The EPR line intensity at g=2.1 was found to be proportional to the concentration of magnetic nanoparticles and the best temperature for spectra acquisition was 298 K. Both EPR and XRF analysis indicated that the maximum concentration of iron in the liver occurred 95 min after the ferro fluid administration. The half-life of the magnetic nanoparticles (MNP) in the blood was (11.6±0.6) min measured by EPR and (12.6±0.6) min determined by XRF. These results indicate that both EPR and XRF are very useful and appropriate techniques for the study of kinetics of ferrofluid elimination and biodistribution after its administration into the organism.