Element Mapping in Organic Samples Utilizing a Benchtop X-Ray Fluorescence Emission Tomography (XFET) System

Abstract

X-ray fluorescence computed tomography (XFCT) is an emerging imaging modality that maps the three-dimensional distribution of elements, generally metals, in <i>ex vivo</i> specimens and potentially in living animals and humans. Building on our previous synchrotron-based work, we experimentally explored the use of a <i>benchtop</i> X-ray fluorescence computed tomography system for mapping trace-metal ions in biological samples. This system utilizes a scanning pencil-beam to stimulate the object and then relies on a detection system, with single or multiple slit apertures placed in front of position-sensitive X-ray detectors, to collect the fluorescence X-rays and to form 3-D elemental map without the need for tomographic imaging reconstruction. The technique was used to generate images of the elemental distributions of a triple-tube phantom and an osmium-stained zebrafish.