Distributions of sulphur and other elements in human hair follicles

Distributions of sulphur and other elements have been measured in several different specimens of human hair follicles. Whole specimens, longitudinal bisections, and 10 μm thick longitudinal sections have been analyzed by PIXE using the Melbourne scanning proton microprobe. Elemental maps consistently showed that sulphur contents of the presumptive hair shaft (PHS) were uniformly low from 0 to 400 μm (bulb end), increased continuously from about 400 to 800 μm, and reached a plateau. Sulphur levels were uniformly low in the inner rooth sheath. These observations are consistent with previous protein analysis of PHS sections, indicating sequential synthesis of the major classes of keratin proteins. Maps of other elements indicated that Si, Ca, and Fe tended to be concentrated randomly, whereas, P, Cl, K, and Zn were more uniformly distributed. Average relative concentrations of Si, P, Cl, K, Ca, Fe, Cu, and Zn were estimated from total X-ray spectra. (orig.)