title: Comparison of protocols measuring diffusion and partition coefficients in the stratum corneum.
abstract: Partition (K) and diffusion (D) coefficients are important to measure for the modelling of skin penetration of chemicals through the stratum corneum (SC). We compared the feasibility of three protocols for the testing of 50 chemicals in our main studies, using three cosmetics-relevant model chemicals with a wide range of logP values. Protocol 1: SC concentration-depth profile using tape-stripping (measures KSC/vand DSC/HSC2, where HSCis the SC thickness); Protocol 2A: incubation of isolated SC with chemical (direct measurement of KSC/vonly) and Protocol 2B: diffusion through isolated SC mounted on a Franz cell (measures KSC/vand DSC/HSC2, and is based on Fick's laws). KSC/vvalues for caffeine and resorcinol using Protocol 1 and 2B were within 30% of each other, values using Protocol 2A were ~two-fold higher, and all values were within 10-fold of each other. Only indirect determination of KSC/vby Protocol 2B was different from the direct measurement of KSC/vby Protocol 2A and Protocol 1 for 7-EC. The variability of KSC/vfor all three chemicals using Protocol 2B was higher compared to Protocol 1 and 2A. DSC/HSC2values for the three chemicals were of the same order of magnitude using all three protocols. Additionally, using Protocol 1, there was very little difference between parameters measured in pig and human SC. In conclusion, KSC/v,and DSCvalues were comparable using different methods. Pig skin might be a good surrogate for human skin for the three chemicals tested. Copyright © 2017 The Authors Journal of Applied Toxicology published by John Wiley & Sons Ltd.
authors.affiliation: Procter & Gamble Service GmbH, (currently HFC Prestige Service Germany GmbH), Berliner Allee 65, 64295, Darmstadt, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Rothe
authors.affiliation: Procter & Gamble Inc., Mason Business Center, Mason, OH, 45040, USA.
authors.forename: C
authors.initials: C
authors.lastname: Obringer
authors.affiliation: Procter & Gamble Inc., Mason Business Center, Mason, OH, 45040, USA.
authors.forename: J
authors.initials: J
authors.lastname: Manwaring
authors.affiliation: L'Oreal Research & Innovation, 1, avenue Eugène Schueller, 93601, Aulnay-sous-Bois, France.
authors.forename: C
authors.initials: C
authors.lastname: Avci
authors.affiliation: L'Oreal Research & Innovation, 1, avenue Eugène Schueller, 93601, Aulnay-sous-Bois, France.
authors.forename: W
authors.initials: W
authors.lastname: Wargniez
authors.affiliation: L'Oreal Research & Innovation, 1, avenue Eugène Schueller, 93601, Aulnay-sous-Bois, France.
authors.forename: J
authors.initials: J
authors.lastname: Eilstein
authors.affiliation: Cosmetics Europe, Avenue Herrmann-Debroux 40, B-1160, Brussels, Belgium.
authors.forename: N
authors.initials: N
authors.lastname: Hewitt
authors.affiliation: Unilever, Colworth Science Park, Sharnbrook, Bedford, MK44 1LQ, UK.
authors.forename: R
authors.initials: R
authors.lastname: Cubberley
authors.affiliation: Pierre Fabre Dermo-Cosmétique, 3, avenue Hubert Curien, 31035, Toulouse Cedex 1, France.
authors.forename: H
authors.initials: H
authors.lastname: Duplan
authors.affiliation: Beiersdorf AG, Unnastrasse 48, D-20245, Hamburg, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Lange
authors.affiliation: Pierre Fabre Dermo-Cosmétique, 3, avenue Hubert Curien, 31035, Toulouse Cedex 1, France.
authors.forename: C
authors.initials: C
authors.lastname: Jacques-Jamin
authors.affiliation: Cosmetics Europe, Avenue Herrmann-Debroux 40, B-1160, Brussels, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Klaric
authors.affiliation: Beiersdorf AG, Unnastrasse 48, D-20245, Hamburg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Schepky
authors.affiliation: L'Oreal Research & Innovation, 1, avenue Eugène Schueller, 93601, Aulnay-sous-Bois, France.
authors.forename: S
authors.initials: S
authors.lastname: Grégoire
mesh_terms: D000328:Adult; D000818:Animals; D002110:Caffeine / Q000378:metabolism; D003358:Cosmetics / Q000737:chemistry* / Q000378:metabolism*; D003374:Coumarins / Q000378:metabolism; D004058:Diffusion / Q000187:drug effects; D004817:Epidermis / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D023421:Models, Animal; D008954:Models, Biological; D010539:Permeability / Q000187:drug effects; D012118:Resorcinols / Q000378:metabolism; D012869:Skin Absorption / Q000187:drug effects*; D013552:Swine
chemical_list: D003358:Cosmetics; D003374:Coumarins; D012118:Resorcinols; C017299:7-ethoxycoumarin; D002110:Caffeine; C031389:resorcinol
keywords: coefficients; comparison; diffusion; partition; protocols; stratum corneum