BONGIOVANNI guillermina Azucena
congresos y reuniones científicas
Multielemental mapping by low-cost EDXRF and μXRF using synchrotron radiation of biological samples
Cabo Frio, Rio de Janeiro,
Congreso; XI Latin American Seminary of Analysis by X-Ray Techniques –; 2008
Institución organizadora:
Society of Analysis by X-Ray Techniques
Synchrotron microscopic XRF (SR-ìXRF), a trace-level microanalytical method, allows quantitative study of biological and biomedical samples, foods, surface treatment characterization, polymers and cosmetics. This microbeam method is able to implement multi-elemental spectrochemical analysis with spatial resolution on the micrometer scale. Contrary to the expectation there are not very many synchrotron facilities to meet the huge demands of numerous users. This is due to the high costs (hundreds of millions US$) and the required optimum technological expertise. Currently, around the world there are about fifty storage rings in operation as synchrotron radiation sources, located in twenty-three countries. The Brazilian Synchrotron Light Laboratory (LNLS), installed in Campinas, is the only one of its kind in the Southern Hemisphere. In this work, multielemental maps of rat organs obtained by EDXRF using a FISCHER XDAL spectrometer with a 50 keV tungsten-anode x-ray tube as radiation source were compared with those previously obtained ìXRF using synchrotron with 1.37 GeV of energy source [1-3]. For that, the animals were divided in two groups: control and hydroarsenicism rat model. The last group received drinking water containing 100 ppm of NaAsO2 ad libitum for 60 days. The organs were removed, cut in slices of 2 mm thickness, lyophilized and then fixed in acrylic resin. The XRF spectrograms were guided into the DO09B-XRF beamline at the LNLS or at the Institute of Earth Sciences “Jaume Almera” by a FISCHER XDAL equipment and mapping of x-ray fluorescence intensities were done. In Figure 1, As and Fe maps are shown as representative results. Complete results will be reported in this Seminary. We conclude that low-cost EDXRF equipments are successful tools for the routine characterization of biological samples