Magnetic resonance imaging (MRI) is the most frequently used technique for serial
in vivo cell tracking applications due to high resolution of soft tissues, which makes it especially useful for imaging of the brain, muscles, or the heart.¹ In order to improve detectability of transplanted cells and produce a strong contrast against surrounding tissue, intracellular labeling of cells with iron oxide particles before transplantation has been described.² FeraTrack Direct Contrast Particles are SPIO nanoparticles specifically formulated for direct uptake from cell culture medium without the need of transfection reagent. Uptake of FeraTrack Direct Contrast Particles was proven by Prussian Blue staining, MRI, and electron microscopy. Biocompatibility was assured by cell expansion and differentiation assays of intracellularly labeled cells. Once within cells, SPIOs can induce decreased signal intensity on T1, T2, and T2*-weighted images.³
