An application of micro X-ray fluorescence computed tomography for the determination of three-dimensional elemental distribution in a single hair strand

Three-dimensional imaging of trace elements in a single hair strand was achieved by a micro X-ray fluorescence computed tomography (mu XRF-CT) using synchrotron radiation. A simple rotational mechanism was attached to a two-dimensional XRF imaging system and a wide range of longitudinal scans was realized. The experimental determination of centroid of projections helped to maintain the spatial resolution around 2 mu m that was determined by the beam size. Determination of trace element concentration in a single hair strand was realized by combining measurements of both scattered X-ray and XRF intensities, and longitudinal changes in concentration were observed. Cross-sectional distribution of Br, Zn, Fe and Cu were obtained at the positions of interest after the longitudinal scan, and changes in distribution forms were observed.

Automated summary

This study utilized micro X-ray fluorescence computed tomography (mu XRF-CT) to achieve three-dimensional imaging of trace elements in a single hair strand. Experimental determination of trace element concentration and observation of longitudinal changes were carried out successfully. Cross-sectional distribution of Br, Zn, Fe, and Cu were obtained and changes in distribution forms were also observed.