Comparison of Gold Nanoparticles and Iodinated Contrast Media in Radiation Dose Reduction and Contrast Enhancement in Computed Tomography

Abstract

Background: Gold nanoparticles with high atomic number and density have good potential to be used as contrast media in computed tomography. Objectives: In this study, we aimed to assess radiation dose and contrast enhancement performance of gold nanoparticles by measuring contrast to noise ratio compared to clinically used iodinated contrast agents at same concentrations. Contrast enhancement was evaluated in different tube voltages and currents. Materials and Methods: First, polyethylene glycol coated gold nanoparticles were synthesized with concentrations of 0.5 mM, 0.6 mM, and 0.7 mM. Gold nanoparticles and iodinated contrast media were scanned with CT imaging system at different tube voltages and time-current product. CT dose index (CTDI) value was measured by special phantom and electrometer. Improving in image contrast was assessed by contrast to noise ratio. Results: Results showed that gold nanoparticles in all concentrations and energies from 80 to 130 kVp display higher image contrastto-noise ratio (CNR) than iodinated contrast media. Image CNR was increased by increasing kVp and mAs. The CNR value was maximum at the voltage of 80 and 130 kVp for iodinated compounds and gold nanoparticles, respectively. The CNR value for gold nanoparticles at 130 kVp and 200 mAs was approximately five times higher than that of iodinated compounds. Conclusion: Gold nanoparticles could be a good candidate for optimizing CT imaging by lowering radiation dose as low as possible while enhancing the image contrast.

Application of Gold Nanoparticles as Radiosensitizer for Metastatic Prostate Cancer Cell Lines

“…Our results from CT imaging demonstrated that AuNPs’ attenuation factor was directly proportional to AuNP concentration. Studies have proposed that AuNPs could be a good candidate as contrast for CT imaging [ 33 , 34 ]. Our results are in accordance with literature results studying a concentration of contrast from 0 to 1 mM [ 22 , 34 , 35 ].…”

“…Studies have proposed that AuNPs could be a good candidate as contrast for CT imaging [ 33 , 34 ]. Our results are in accordance with literature results studying a concentration of contrast from 0 to 1 mM [ 22 , 34 , 35 ]. Previously, studies have reported conflicting results regarding the influence of the size of AuNPs as a contrast agent, but no information was found regarding the shape of AuNPs [ 22 , 33 , 36 ].…”

Nanomaterials: A Promising Therapeutic Approach for Cardiovascular Diseases

“…Detection of atherosclerosis might be improved by using computed tomography agents, such as gold. CNR (contrast-to-noise ratio) of Au-NPs is greater than the commercially available iodinated agent Visipaque TM [83]. However, CT imaging equipment itself entails radiation exposure, and numerous scans in a short period of time are unlikely to be therapeutically feasible.…”

PLGA-Gold Nanocomposite: Preparation and Biomedical Applications

“…Since tissues and biological fluids have low attenuation capability, contrasting agents (typically iodine-based media) are required for resolved CT imaging in clinical practice. However, it was found that GNP could provide more efficient X-ray attenuation (5.16 for GNP compared to 1.94 cm 2 /g for iodine, at 100 keV) and they thus hold true promise in CT imaging [ 31 , 32 , 33 ]. Based on this property, targeted gold nanoprobes have been employed to localize cancer using a standard clinical CT scan [ 34 , 35 ].…”