In this study, we employed several methods to characterize iron-oxide nanoparticles using SQUID magnetometry and MRI. With SQUID magnetometry, we measured the Isothermal Remanent Magnetization of C...Show moreIn this study, we employed several methods to characterize iron-oxide nanoparticles using SQUID magnetometry and MRI. With SQUID magnetometry, we measured the Isothermal Remanent Magnetization of C. Elegans and two human brain samples. We obtained the iron concentration from the fit. We were able to detect changes in iron concentration due to mutations in C. Elegans. For the MRI measurements, we used Quantitative Susceptibility Mapping and an Off-Resonance Saturation method for brain phantoms. These phantoms consist of different concentrations of magnetite or ferritin dissolved in an agarose gel and mimics the human brain. With QSM we observed a comparable slope of the susceptibility/µg iron/ml. For the ORS method, a good agreement is found between the obtained iron concentration and the pre-determined iron concentration in the sample.Show less
The possibly crucial role of the presence of iron nanoparticles in the humain brain, in neuronal diseases such as Alzheimers’ disease makes them interesting subjects for research. In magnetic...Show moreThe possibly crucial role of the presence of iron nanoparticles in the humain brain, in neuronal diseases such as Alzheimers’ disease makes them interesting subjects for research. In magnetic resonance imaging, contrast arises due to the presence of such magnetic entities. In this report we address models that describe the mechanism behind this induced contrast, due to the presence of ferritin and magnetite nanoparticles. We have measured the transverse relaxation T2 and T 2 times using the MSME and MGE sequence. We found a linear decrease in both the relaxation times as a function of particle concentration. Concluded is that the relaxation of the magnetic nanoparticles is dominated by the diffusion of protons surrounding the magnetic nanoparticle, which is described by the motional averaging regime. We used Atomic Force Microscopy and Transmission Electron Microscopy to characterize the sample.Show less
