Heterogeneity effects in direct x‐ray fluorescence analysis of hair

Abstract

The methodology of direct hair analysis by energy‐dispersive x‐ray fluorescence was studied. The effect on the XRF result of having a non‐homogeneous radial distribution of the analyte in a single hair strand and the macroscopic effects in a bundle of hairs were calculated to evaluate possible systematic errors. The detection limits were mapped as a function of the target thickness and surface fraction. It appeared that a 10 mg cm−2 sample thickness, i. e. a target with about four layers of hair strands, is recommended. The standard deviation of this simple direct analytical method is 6–19% for some important elements. Discrepancies with neutron activation analysis had a mean value of around 15%. About twelve elements can be determined simultaneously on a routine basis.

Quantitative EDXRF analysis of Ca, K, Mn and Na in normal and pathological adult-human teeth

“…A major goal for research in biomedical sciences over the last few decades has been to determine the concentrations of various elements in human tissues. In recent years, the large increase in research work related to bio-medical such as blood, human head hair, kidney stones, human teeth and bones have been made it desirable to improve the application of EDXRF analysis [3][4][5]. Also, the X-ray diffraction and X-ray fluorescence technique were used to determine structural properties in different media [6,7].…”