High-spatial-resolution maps of sulphur from human hair sections: an EELS study

High-resolution sulphur maps have been acquired from human hair using a Zeiss CEM 902A transmission electron microscope equipped with an energy filter. Analysis by electron energy-loss spectroscopy (EELS) was performed on ultrathin sections of hair shafts embedded in three different types of resin: Nanoplast (water-soluble), Spurr (epoxy) and Lowicryl (low-temperature resin). Good-quality energy-loss images have been obtained with the three resins, although it was found that Nanoplast gave the best image contrast. For the first time, the results obtained for the detection of sulphur by silver staining of hair sections, which until now has been the only way to map sulphur at the electron microscopic level, have been confirmed. The results are compared with local sulphur concentrations from bulk analysis.