International Journal on Magnetic Particle Imaging IJMPI
Vol. 8 No. 1 Suppl 1 (2022): Int J Mag Part Imag

Proceedings Articles

Optimizing magnetic particle image resolution using superferromagnetic nanoparticles modified through post-synthesis oxidation

Main Article Content

Jacob Bryan , Benjamin Fellows (UC Berkeley), K.L Barry Fung , Prashant Chandrasekharan , Steven Conolly 


Magnetic Particle Imaging (MPI) is a novel tracer-based imaging modality that allows for exquisitely sensitive celltherapy trackingin vivo, cancer imaging, lung ventilation/perfusion imaging, and hemorrhage detection. MPIuses superparamagnetic iron oxide Particles (SPIOs) as tracers with linear contrast, zero tissue attenuation, andmicromolar sensitivity, all with zero ionizing radiation and infinite reporter persistence. However, MPI’s poor spatialresolution (roughly 1 mm in a 7T/m gradient) is holding back clinical translation. Our lab recently reported theuse of superferromagnetic nanoparticles (SFMIOs) for MPI demonstrating a 10-fold improvement (?100?m) inresolution compared to the approximately mm for commercially available SPIOs. In the current work, we detail theproduction of SFMIO for MPI using a modified extended LaMer synthesis. We implement a post-oxidation step tothe process for repeated and reproducible production of high resolution SFMIO particles.

Article Details


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