Iron Oxide Nanoparticles Biodistribution in an Experimental Pig Model – A New Approach for Delivery and Imaging

Iron oxide nanoparticles (IONs) are of great interest in medicine, with great potential for imaging diagnostics, as well as therapeutic. Biomedical applications of IONs have been suggested for magnetic resonance imaging (MRI), with two available contrast agents on the market. However, new developments in biocompatibility and biodistribution are necessary as many new physiochemical features of coatings have been proposed for a good safety profile. Materials and Methods. Our study objective was to assess a different setting in terms of biodistribution of IONs coated with citric acid on an experimental pig model, based on EUS-guided portal vein (PV) injection. Four pigs were subjected to EUS procedures and portal vein injection of an IONs solution. All animals were kept under surveillance for the next 24 hours and euthanized. Necropsy was performed and their organs were harvested, visualized with a 3T MRI scanner and sent to pathological examination. Results. All pigs had no change in their behavior and no signs of complications were encountered. There were no problems in identifying the pig’s PV under EUS-guidance. The IONs solution was clearly visualized on ultrasound live imaging, during EUS-injection. MRI and histopathological data confirmed all the deposits using Prussian Blue staining. Conclusions. This paper comes forward as a first phase of assessing new future therapeutic options and their distribution within the main organs depending on their characteristics. In our opinion this new distribution option has a strong incentive to the research of therapeutic and imaging areas and is worthy of further appraisal.