Synthesis and characterization of PVP-coated large core iron oxide nanoparticles as anMRI contrast agent

Abstract

The purpose of this study was to synthesize biocompatible polyvinylpyrrolidone(PVP)-coated iron oxide (PVP-IO) nanoparticles and to evaluate their efficacy as amagnetic resonance imaging (MRI) contrast agent. The PVP-IO nanoparticles weresynthesized by a thermal decomposition method and characterized by x-ray diffraction(XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS),and a superconducting quantum interface device (SQUID). The core size of theparticles is about 8–10 nm and the overall size is around 20–30 nm. The measuredr2 (reciprocal ofT2 relaxation time)and r2* (reciprocal ofT2* relaxation time)are 141.2 and 338.1 (s mM)−1, respectively. The particles are highly soluble and stable in various buffersand in serum. The macrophage uptake of PVP-IO is comparable to thatof Feridex as measured by a Prussian blue iron stain and phantom study.The signal intensity of a rabbit liver was effectively reduced after intravenousadministration of PVP-IO. Therefore PVP-IO nanoparticles are potentially useful forT2-weighted MR imaging.