Preparación de muestras sólidas para el análisis por fluorescencia de rayos X: una revisión.

X-ray fluorescence (XRF) allows multielement analysis to be performed on a variety of solid matrices, including powders and grains. To obtain reliable results, the sample must meet certain criteria related to its thickness, surface flatness, homogeneity and particle size. Heterogeneous solid samples to be measured must be pulverized, homogenized, and prepared as loose powder, pressed powders (pellets) or fused beads, if accurate and reproducible measurements are sought. The measurement conditions are defined by the analytical depth of the fluorescent X-rays of the analytes, and can be estimated from the relationship between the absorption of each beam and its respective energy, and the composition and density of the sample. Furthermore, in purpose of assuring the validity of the results, the measurement method must be validated to confirm that it fulfills the purpose for which it was developed. This review is focused on the preparation of solid samples, the quantitative analysis, which includes the validation of the methods involved in XRF spectrometry measurements, and on the main applications of the technique. [ABSTRACT FROM AUTHOR]