| AVS 55th International Symposium & Exhibition | |
| Magnetic Interfaces and Nanostructures | Wednesday Sessions |
| Session MI+NC-WeM |
| Session: | Magnetic Thin Films, Nanoparticles and Nanostructures |
| Presenter: | K. Uvdal, Linköping University, Sweden |
| Authors: | M. Ahren, Linköping University, Sweden L. Selegard, Linköping University, Sweden N. Abrikossova, Linköping University, Sweden A. Klasson, Linköping University, Sweden F. Soderlind, Linköping University, Sweden M. Engstrom, Linköping University, Sweden P.-O. Käll, Linköping University, Sweden K. Uvdal, Linköping University, Sweden |
| Correspondent: | Click to Email |
The properties of very small particles, i.e. particles with a small volume to surface relative ratio, have been shown to clearly differ from both the atom and bulk material. Such low dimensional materials will be of main importance during material design and optimization in the future. We are now designing functionalized rare earth nanocrystals and this material is very promising as positive contrast agent in Magnetic Resonance Imaging (MRI). The core of the nanomaterial is characterized using X-ray Photoelcetron Spectroscopy (XPS), Transmission Electron Microscopy (TEM) and Photo Emission Electron Microscopy (PEEM). The functionalization steps are investigated by means of XPS, Infrared (IR) Spectroscopy and Dynamic Light Scattering (DLS). The proton relaxation times were measured as a function of dialysis time and functionalization, with a MRI scanner. The relaxivity is compared to commercially available Gd based chelates (Gd-DTPA). We have shown that the core consists of pure Gd2O3, the particles are crystalline and in the size of about 3-5 nm. The functionalization process and dialysis procedure are shown to increase the stability of the material. A considerable relaxivity increase for functionalized and dialyzed particles compared to corresponding values for Gd-DTPA is obtained. The long term goal is to design a powerful, directed contrast agent for MRI examinations with specific targeting possibilities with strong MR- signal on the cell- and molecular level.