The lipid and keratin structure of pig stratum corneum has been elucid
ated by small- and wide-angle X-ray diffraction. The measurements were
carried out as a function of hydration and temperature. In addition,
the stratum corneum was measured after recrystallization of the lipids
at various temperatures. The results led us to conclude that the inte
rcellular lipids in the stratum corneum are organized in at least two
different lamellar structures with repeat distances of 6 and 13.2 nm.
There is an indication for the presence of a third phase with a period
icity of 9 nm. The wide-angle pattern revealed a hexagonal (0.414 nm s
pacing) and liquid lateral packing (approximate to 0.46 nm spacing). T
he 0.414 nm reflection started to decrease in intensity between 60 and
66 degrees C and disappeared between 72 and 95 degrees C. Furthermore
, crystalline cholesterol has been indicated by both, wide- and small-
angle X-ray diffraction, while the reflections of alpha-keratin were o
bserved in the wide-angle X-ray diffraction pattern.