Raman Microscopy and Imaging: Applications to Skin Pharmacology and Wound Healing - Emerging Raman Applications and Techniques in Biomedical and Pharmaceutical Fields - page 361

Fig. 15.2. a Schematic of the “bricks and mortar” stratum corneum model. The cor-
neocytes, depicted as hexagons, are embedded in a lipid matrix background. Scale
bar = 10 μm. b AFM micrograph of a corneocyte. The corneocyte is a flattened
cell with x , y , dimensions of ∼ 50 μm and irregular thickness ranging to 700 μm.
c Packing motifs and chain conformations of lipid bilayers. The orthorhombic phase
and hexagonal phase chains are both conformationally highly ordered, while the liq-
uid crystalline phase contains conformationally disordered chains. The liquid crys-
talline state occurs rarely if at all in the SC. The bottom half of the figure attempts
to diagram the progressive loosening of chain packing in going from orthorhombic
to hexagonal to liquid crystalline phases. C-C bonds are shown (in projection) as
viewed through planes drawn parallel to the bilayer plane in the region of the lipid
chains in the top half of the figure