STABILITY ANALYSIS OF SUPERPARAMAGNETIC IRON OXIDE NANOPARTICLES (SPIONs) AT 37 °C

Superparamagnetic Iron Oxide Nanoparticles (SPIONs) are used in a variety of medical applications, for example as tracer material for Magnetic Particle Imaging (MPI), contrast agents for MRI, or for hyperthermia in cancer therapy. Especially for the use in patients, the particle stability is essential to prevent vascular occlusions and to ensure good MPI signals. SPIONs with a dextran coating were synthesized using alkaline precipitation and kept in 37 degrees C at different pH values for 6 weeks to analyse their stability over a long time period. The particles kept at pH 7.2 were stable for five weeks, whereas the particles at pH 6.2 showed aggregation after 2 weeks.