Gd2O3–Carbon Nanoflakes (CNFs) as Contrast Agents for Photon-Counting Computed Tomography (PCCT)

Abstract

2–3 nm Gd2O3 nanoparticles deposited on carbon nanoflakes were prepared. These are new contrast agents for photon-counting computed tomography based on detectors allowing counting of separate photons. Contrast agents of the Gd2O3@C core–shell structure were prepared by graphitization of the surface of these particles. The Gd2O3 and Gd2O3@C nanoparticles obtained, aqueous solution of Gd(NO3)3·6H2O, and a dispersion of 300–500 nm Gd2O3 particles in gelatin were studied by photon-counting computed tomography. At equal gadolinium concentrations, the highest X-ray absorption was noted for Gd(NO3)3·6H2O and Gd2O3, which is associated with higher density of these samples. Carbon in the contrast agents does not affect the absorption. An algorithm was developed for semiquantitative determination of gadolinium by photon-counting computed tomography.