Abstract
Background. Because ionizing radiation and radioactive materials are not used in MRI images and their good spatial resolution, it has been widely used in the diagnosis of diseases. But for a more accurate diagnosis of some diseases, it is necessary to inject contrast material. Contrast materials are metal ions of paramagnetic elements such as gadolinium (Gd) or superparamagnetic iron oxide nanoparticles (SPIONs). This study aims to investigate the effect of echo time (TE) on the signal intensity of PVP-grafted iron oxide nanoparticles on spin echo T2-weighted images as a negative contrast material (T2-contrast).
Methods. Prepared nanoparticles (SPIONs grafted with PVP) in different concentrations (0-0.600 μmol Fe/L) that were poured inside the test tubes were spin echo T2-weighted imaged by an MRI scanner (1.5 T).
Results. The curves of nanoparticle concentration versus the signal intensity show that with increasing nanoparticle concentration, the signal intensity decreases. Also, at a constant TE, the higher nanoparticle concentration has lower signal intensity.
Conclusion. The produced nanoparticle (PVP-grafted iron oxide nanoparticles) can be used in clinical work as a negative contrast material due to the behaviour it showed in different concentrations and TE.
Practical Implications. Nanoparticles are used as a contrast agent in MRI imaging. The results of this study show that the prepared contrast agent can be used as a negative contrast agent in clinical imaging.