Determination of trace elements in organic matrices by grazing-emission X-ray fluorescence spectrometry

Grazing-emission X-ray fluorescence spectrometry (GEXRF) was used for the d etermination of trace amounts of Na, Zn and Pb in an organic matrix. Specia l attention was paid to deposit sample layers with a thickness below a cert ain critical level, on polycarbonate carriers, in order to avoid matrix eff ects and to obtain straight calibration curves. Detection limits (DL's) for a low-Z element (Na), a medium-Z element (Zn) and a heavy-Z element (Pb) i n such kind of material are calculated and amount to 0.4, 1.5 and 2 ng, res pectively. In order to demonstrate the simplicity by which trace elements i n organic material can be analysed with GEXRF, the analysis of beer samples was performed. (C) 1999 Elsevier Science B.V. All nights reserved.