Utilization of Innovative Hydroxyapatite-Coated Gd2O3@Bi2O3 Nanocomposite as a Bifunctional Material for Magnetic Resonance Imaging and Computed Tomography

Recently, different nanostructures have been investigated as contrast agents for bimodal magnetic resonance imaging/computed tomography (MRI/CT). In this study, the potentiality of the combined form of the Gd2O3, Bi2O3, and hydroxyapatite (HA) nanoparticles for bimodal MRI/CT was examined because of their individual properties. For this purpose, Gd2O3@Bi2O3–HA nanocomposite was synthesized via a two-step method. The structure, size, magnetic property, and the cell viability of the nanocomposite were investigated. MRI and CT were performed to determine the relevant relaxivities and the X-ray attenuation of the nanocomposite, respectively. The paramagnetic nanocomposite had a spherical shape with a size of 20–30 nm. The cell viability data confirmed the cytocompatibility of the nanocomposite. The r1 and r2 relaxivities were calculated as 33.41 and 59.33 mM−1 s−1, respectively, leading to an r2/r1 of 1.7. The r1 relaxivity and the X-ray attenuation of the nanocomposite were higher than those of the commercial contrast media. This study suggests that Gd2O3@Bi2O3–HA nanocomposite, as a novel nanomaterial, has excellent potential for bimodal T1-weighted MRI and CT.