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EN
Synchrotron radiation-induced X-ray emission is now a proven analytical method for the determination of trace elements. Better insight of the role of trace elements in tissue samples can be gained by acquiring complete distribution maps of these elements. Our approach is based on the acquisition of digital maps. In this contribution we present two different methods for obtaining normalization matrix: first - based on argon intensity in the single spectrum and second - based on changes of beam current intensity. The region for the scan was carefully chosen according to the histological view of the sample. A total area was scanned with a step size of 15 μm in each direction and measuring time of 30 s per pixel. The thickness of the samples was 15 μm. A polycapillary was used for beam focusing. At the energy of 18 keV the beam size on the sample was approximately 15 μm which is of the order of a cell diameter.
EN
Sulphur is vital for almost all living organisms by participating in a wide variety of metabolic processes. Nevertheless its biochemistry is only partially understood, due to it a few tools such as X-ray absorption near edge structure may be used to determine its chemical speciation in biological system. In this paper we focused on analysis of composition and elemental distribution in tissue structures of biological samples. We examined cancerous and non-cancerous prostate tissues. Experiments were carried out on the L-beam line at the HASYLAB, DESY (Hamburg, Germany) and DAΦNE-Light Facility at the Laboratori Nationali di Frascati (Frascati, Italy). Synchrotron radiation induced X-ray emission measurements reveal the significant differences in concentration of sulphur between cancerous and non-cancerous tissues. X-ray absorption near edge structure spectra show two main types of sulphur that are represented by X-ray peaks at 2476 eV and 2484 eV. This suggests that different sulphur components are present in the measured samples.
EN
The prostate gland is the most common site of neoplastic disorders in men. The knowledge of the pathogenesis of benign prostate hyperplasia and prostate cancer is still under investigation. X-ray fluorescence analysis using synchrotron radiation seems to be an appropriate technique to study the elemental composition of biological tissues. The measurements presented in this paper were carried out on the L-beam line at the HASYLAB, DESY (Germany). The observed concentrations of Fe, Cu, Mn, and Zn are significantly higher in cancerous tissues, as compared to normal and hyperplastic ones. Our results reveal also the existence of the two types of hyperplasia.
EN
We review hard X-ray microscopy techniques with a focus on scanning microscopy with synchrotron radiation. Its strength compared to other microscopies is the large penetration depth of hard x rays in matter that allows one to investigate the interior of an object without destructive sample preparation. In combination with tomography, local information from inside of a specimen can be obtained, even from inside special non-ambient sample environments. Different X-ray analytical techniques can be used to produce contrast, such as X-ray absorption, fluorescence, and diffraction, to yield chemical, elemental, and structural information about the sample, respectively. This makes X-ray microscopy attractive to many fields of science, ranging from physics and chemistry to materials, geo-, and environmental science, biomedicine, and nanotechnology. Our scanning microscope based on nanofocusing refractive X-ray lenses has a routine spatial resolution of about 100 nm and supports the contrast mechanisms mentioned above. In combination with coherent X-ray diffraction imaging, the spatial resolution can be improved to the 10 nm range. The current state-of-the-art of this technique is illustrated by several examples, and future prospects of the technique are given.
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