Electron paramagnetic resonance (EPR) spectra of nitroxide spin probes are
useful for studying biological membranes and chemical-membrane interactions
. Recently, we established a stripping method to remove stratum corneum (SC
) for this purpose. To assess this stripping method with EPR and correlate
with standard methods, we quantified the irritant effects of three types of
surfactants by measurements of Visual score and transepidermal water loss
(TEWL), SC hydration and chromametry and studied EPR spectra measurements o
f surfactant-treated cadaver SC (C-SC) and stripped off SC (S-SC) on patch
tested sites. 5-Doxyl stearic acid was the spin label. The order parameter
S obtained from the spectra of S-SC correlated with those of C-SC and TEWL
values. The results suggest that this method is capable of evaluating the f
luidity of SC and correlates with the above bioengineering parameters. (C)
2000 Elsevier Science B.V. All rights reserved.