Figure 4

Interactions of the studied enhancers Pro2, Pro3, and Pro4 with human stratum corneum examined by infrared spectroscopy: methylene symmetric stretching wavenumbers indicative of decreased lipid chain order (A), amide I band with no significant effect on protein conformation (B), and relative intensities of the methylene symmetric stretching band to amide I band indicating no significant lipid extraction (C). Data are presented as the means ± SEM; n ≥ 3. *Statistically significant difference compared to control (60% PG without enhancer) at p < 0.05.