Synthesis and Application of Fe۳O۴@Au Composite Nanoparticles as Magnetic Resonance/Computed Tomography Dual‑Modality Contrast Agent

Background: None of the molecular imaging modalities can produce imaging with both anatomical and functional information. In recent years, to overcome these limitations multimodality molecular imaging or combination of two imaging modalities can provide anatomical and pathological information. Methods: Magnetic iron oxide nanoparticles were prepared by co‑precipitation method and then were coated with silica according to Stober method. Consequently, silica‑coated nanoparticles were amino‑functionalized. Finally, gold nanoparticles assembled onto the surfaces of the previous product. Cytotoxicity effects of prepared Fe۳O۴@Au nanoparticles were evaluated by ۳‑(۴,۵‑dimethylthiazol‑۲‑yl)‑۲,۵‑diphenyltetrazolium bromide assay on human hepatocellular carcinoma cells. Their ability as a dual‑mode contrast agent was investigated by magnetic resonance (MR) and computed tomography (CT) imaging. Results: Fe۳O۴@Au nanoparticles were spherical undersize of ۷۵ nm. X‑ray diffraction analysis confirmed the formation of Fe۳O۴@Au nanoparticles. The magnetometry result confirmed the superparamagnetism property of prepared nanoparticles, and the saturation magnetization (Ms) was found to be ۳۳ emu/g. Fe۳O۴@Au nanoparticles showed good cytocompatibility up to ۶۰ μg/mL. The results showed that the Fe۳O۴@Au nanoparticles have good r۲ relaxivity (۱۳۵.۲۶ mM−۱s−۱) and good X‑ray attenuation property. Conclusion: These findings represent that prepared Fe۳O۴@Au nanoparticles in an easy and relatively low‑cost manner have promising potential as a novel contrast agent for dual‑modality of MR/CT imaging.

کلیدواژه ها:

Computed tomography ، gold nanoparticles ، iron oxide nanoparticles ، magnetic resonance imaging