To clarify and visualize skin penetration, we used DiI,
which has a molecular weight of 834 Da and a log P of 23.2.
Figure 4 shows CLSM images of cross-sections of YMP skin
after exposure to O/W emulsions. DiI penetration into the
stratum corneum differed significantly, with LP-A>LP-C (Fig.
4). This phenomenon was also evident with regard to SG.