Use of red blood cells as new strategy to avoid the rapid clearance of SPIOs nanoparticles

The advantage of SPIO-loaded RBCs is that they are stable constructs able to survive for a number of days without being eliminated and with a lifespan comparable to that of untreated RBCs. The potential of RBCs loaded with SPIO nanoparticles has been previously investigated as a tracer material for magnetic particle imaging (MPI), a new quantitative medical imaging modality recently introduced by Philips showing that it is possible to detect a beat heart in mice. These data make SPIO-loaded RBCs ideally suited to increase the in vivo circulation of SPIO contrast agents as longer blood half-time tracer materials improving diagnostic imaging procedures, such as angiography analysis of patients with cardiovascular diseases and therapeutic interventions with long-term monitoring, since up to now the time window for data acquisition is limited to the first pass due to very short lifespan of iron oxide nanoparticles.