Strat-M® positioning for skin permeation studies: A comparative study including EpiSkin® RHE, and human skin
Résumé
In the development and optimization of dermatological products, In Vitro Permeation Testing (IVPT) is pivotal
for controlled study of skin penetration. To enhance standardization and replicate human skin properties
reconstructed human skin and synthetic membranes are explored as alternatives. Strat-M® is a membrane
designed to mimic the multi-layered structure of human skin for IVPT. For instance, in Strat-M®, the steady-state
fluxes (JSS) of resorcinol in formulations free of permeation enhancers were found to be 41 ± 5 μg/cm2⋅h for the
aqueous solution, 42 ± 6 μg/cm2⋅h for the hydrogel, and 40 ± 6 μg/cm2⋅h for the oil-in-water emulsion. These
results were closer to excised human skin (5 ± 3, 9 ± 2, 13 ± 6 μg/cm2⋅h) and surpassed the performance of
EpiSkin® RHE (138 ± 5, 142 ± 6, and 162 ± 11 μg/cm2⋅h). While mass spectrometry and Raman microscopy
demonstrated the qualitative molecular similarity of EpiSkin® RHE to human skin, it was the porous and hydrophobic
polymer nature of Strat-M® that more faithfully reproduced the skin’s diffusion-limiting barrier.
Further validation through similarity factor analysis (~80–85%) underscored Strat-M®’s significance as a reliable
substitute for human skin, offering a promising approach to enhance realism and reproducibility in
dermatological product development.