Preliminary Evaluation of Bismuth Oxide Nanoparticles (BiONPs) as a Contrast Agent in Diagnostic Imaging

Abstract

Iodine-based contrast agents have been preferred in diagnostic imaging for their effective X-ray attenuation, but they might pose risks such as kidney failure and thyroid dysfunction in certain groups of patients. Bismuth-based nanoparticles have been proposed as a novel CT contrast agent. Therefore, this study aims to evaluate the impact of bismuth oxide nanoparticles (BiONPs) in enhancing image contrast, compared to conventional iodinated contrast agents (ICAs). Iodixanol and BiONPs suspensions were equalized based on their concentrations (50-150 μMol/L). The samples were irradiated with a conventional X-ray imaging unit at various tube potentials ranging from 46 to 125 kVp. The contrast-to-noise ratio (CNR) is used to calculate contrast enhancement. The findings indicate that BiONPs and ICAs exhibit closely aligned CNR trends with less than 10% difference across tube potentials (46 to 90 kVp). However, a key distinction emerges at higher tube potentials (125 kVp) and concentrations (100 to 150 μMol/L), where BiONPs demonstrated superior contrast enhancement. This study found a comparable comparison between BiONPs and ICAs, which suggests that BiONPs can attain the proven efficacy of ICAs in standard clinical imaging scenarios. In conclusion, the ability of BiONPs to obtain high CNR values at concentrations comparable to those used in ICAs suggests increased diagnostic accuracy with potentially lower doses, lowering toxicity risks.