Current Views on Noninvasive in vivo Determination of Physiological Parameters of the Stratum Corneum Using Confocal Raman Microspectroscopy

Skin Pharmacology and Physiology

Review Article

Free Access

Darvin M.E.a,b· Schleusener J.a· Lademann J.a· Choe C.-S.c

Author affiliations

aDepartment of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology (CCP), Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
bSaratov State University, Institute of Physics, Saratov, Russian Federation
cKim Il Sung University, Pyongyang, Democratic People's Republic of Korea

Corresponding Author

Maxim E. Darvin, maxim.darvin@charite.de

Abstract

Confocal Raman microspectroscopy is widely used in dermatology and cosmetology for analysis of the concentration of skin components (lipids, natural moisturizing factor molecules, water) and the penetration depth of cosmetic/medical formulations in the human stratum corneum (SC) in vivo. In recent years, it was shown that confocal Raman microspectroscopy can also be used for noninvasive in vivo depth-dependent determination of the physiological parameters of the SC, such as lamellar and lateral organization of intercellular lipids (ICLs), folding properties of keratin, water mobility, and hydrogen bonding states. The results showed that the strongest skin barrier function, which is primarily manifested by the orthorhombic organization of ICLs, is provided at ≈20–40% SC depth, which is related to the maximal bonding state of water with surrounding components in the SC. The secondary and tertiary structures of keratin determine water binding in the SC, which is depth-dependent. This paper shows the technical possibility and advantage of confocal Raman microspectroscopy in noninvasive investigation of the skin and summarizes recent results on in vivo investigation of the human SC.

© 2022 S. Karger AG, Basel

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Abstract of Review Article

Received: July 29, 2021
Accepted: December 08, 2021
Published online: January 10, 2022

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