X-ray microcomputed tomography as a tool for the investigation of the biodistribution of magnetic nanoparticles.

Computed tomography is a widely used technique to study the inner structure of opaque samples using the material-dependent attenuation of x-rays. Microcomputed tomography follows the same principles used for conventional medical CT scanners, but improves the spatial resolution to a few micrometers. As an example for the application of x-ray microtomography, the study of the 3D biodistribution of magnetic nanoparticles in tumoral tissue after minimal invasive cancer therapy, which is one of the crucial factors for this kind of therapy, is presented in this article. In particular, the possibilities and problems resulting from the use of different sources of radiation--synchrotron and x-ray tubes, respectively--will be discussed.