Laboratory total reflection X-ray fluorescence analysis for low concentration samples

Quantitative elemental determination for concentrations in the ppb range requires a careful preparation of the sample. In particular, for elemental analysis of very low concentration samples, less than 1 ng/mm², a very bright X-ray source, typically synchrotron radiation (SR) in total external reflection fluorescence regime (SR-TXRF), is required. Here, we wish to demonstrate that a conventional source combined with a polycapillary semi-lens can provide a quasi-parallel beam intense enough for desktop TXRF analysis of low concentration samples. - Highlights: • Total Reflection X-ray Fluorescence for very low concentration analisys. • Qualitative and quantitative information from trace elements in the ppb range. • Conventional source with polycapillary optics instead Synchrotron Radiation. • Possibility to perform the technique in all kind of laboratories