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Updated: Sep 26, 2026

Visualizing and Quantifying Pharmaceutical Compounds within Skin using Coherent Raman Scattering Imaging
Published on: November 24, 2021
[Follicular penetration. An important pathway for topically applied substances]
J Lademann1, N Otberg, H Richter
1Klinik für Dermatologie und Allergologie, Medizinische Fakultät Charité, Berlin. jürgen.lademann@charite.de
Abstract:
The knowledge of penetration pathways in and through the skin is a prerequisite for the development and optimization of topically applied drugs and cosmetics. Skin penetration has been assumed to occur via diffusion though the lipid domains of the stratum corneum. Recent studies show that the skin appendages, especially the hair follicles, play an important role in skin penetration processes. Topically applied substances cannot enter all follicles. We discuss the reasons for the phenomenon of open and closed hair follicles.
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