Assessment of low energy X-ray imaging for magnetic and gold nanoparticles

Abstract

Introduction Gold and magnetic nanoparticles (NPs) are already used as contrast agents in CT and MRI diagnosis respectively, as well as in hyperthermia treatments. In both cases it is very important to be able to determine in vivo the distribution of the NPs. This can be done by radiolabeling the NPs or via MRI. These methods however present serious drawbacks in terms of cost and complexity. Purpose The purpose of this study is to explore and standardize a procedure of in vivo X-ray imaging for magnetic and gold NPs for diagnostic and pre-therapeutic purposes, using this low-cost, simple, readily available technology. Materials and methods The measurements were carried out on a prototype bench top x-ray system, consisting of an X-ray tube of a maximum beam energy of 80 keV and a minimum focal spot of 33 μm and of a CMOS detector with an active area of 12 × 12 cm and a spatial resolution of 0.1 mm. NPs samples of concentrations ranging between 1 and 500 mg of substance/ml were studied and compared with standard iodine solutions. Results All substances are found to present significant contrast enhancement properties and are used to create a standardized imaging procedure with respect to their concentrations. Gold nanoparticles are easily seen in lower concentrations and dual energy subtraction offers a greater differentiation in the observed attenuation properties. Localization and distribution information can be obtained in vivo through X-ray imaging. Conclusion A standardized procedure of in vivo X-ray imaging is set up for magnetic and gold NPs for diagnostic and pre-therapeutic purposes. Disclosure There is no relationship to be disclosed that may bias this presentation.