Gram scale synthesis of magnetite nanoparticles optimized for single-core MPI tracers

Magnetite nanoparticles with diameters of about 25-30 nm are promising candidates for magnetic particle imaging tracers. When preparing single-core tracers, controlling nanoparticle size and size distribution are critical. Thermal decomposition approaches can produce monodisperse nanoparticles over a range of sizes, but the reactions are kinetically driven monodisperse nanoparticles over a range of sizes, but the reactions are kinetically driven and sensitive to fluctuations that yield batch-to-batch variation in size and quality. Furthermore, if not carefully controlled, the reaction chemistry can produce variations in iron oxide phase and phase purity. Published protocols typically provide examples performed at small-scale and procedures that may not be scalable and frequently omit magnetic characterization that is critical for establishing suitability for MPI. Here, a scalable procedure for producing high quality, single-core magnetite nanoparticles that are confirmed to be suitable for MPI after rigorous characterization is presented. This work demonstrates that thermal decomposition synthesis of MPI tracers can be scaled without compromising quality to enable pre-clinical animal safety and efficacy studies.