Analysis of human blood serum and human brain samples by total reflection X-ray fluorescence spectrometry applying Compton peak standardization

The method of using the Compton peak as internal standard in total reflecti on X-ray fluorescence (TXRF) determination is established for trace element determination of Fe, Cu, Zn, Se and Pt in human serum and of Cu and Zn in homogenized brain samples. A new method of spectrometer sensitivity calibra tion using spiked matrices with known amounts of trace elements is tested a gainst established methods of matrix matching as well as internal element a ddition. The analytical results with the proposed procedure are compared to a certified international standard and to values with Atomic Absorption Sp ectrometry (AAS) obtaining analytical results of comparable accuracy and pr ecision. The method is adequate for routine clinical analysis as it has the advantages of requiring very small amounts of material and simple preparat ions, which avoids the chemical digestion stage. (C) 1999 Published by Else vier Science B.V. All rights reserved.