title: Finite dose skin mass balance including the lateral part: comparison between experiment, pharmacokinetic modeling and diffusion models.
abstract: This work investigates in vitro finite dose skin absorption of the model compounds flufenamic acid and caffeine experimentally and mathematically. The mass balance in different skin compartments (donor, stratum corneum (SC), deeper skin layers (DSL), lateral skin parts and acceptor) is analyzed as a function of time. For both substances high amounts were found in the lateral skin compartment after 6h of incubation, which emphasizes not to elide these parts in the modeling. Here, three different mathematical models were investigated and tested with the experimental data: a pharmacokinetic model (PK), a detailed microscopic two-dimensional diffusion model (MICRO) and a macroscopic homogenized diffusion model (MACRO). While the PK model was fitted to the experimental data, the MICRO and the MACRO models employed input parameters derived from infinite dose studies to predict the underlying diffusion process. All models could satisfyingly predict or describe the experimental data. The PK model and MACRO model also feature the lateral parts.
authors.affiliation: Biopharmaceutics and Pharmaceutical Technology, Saarland University, Saarbruecken, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Selzer
authors.forename: T
authors.initials: T
authors.lastname: Hahn
authors.forename: A
authors.initials: A
authors.lastname: Naegel
authors.forename: M
authors.initials: M
authors.lastname: Heisig
authors.forename: K H
authors.initials: KH
authors.lastname: Kostka
authors.forename: C M
authors.initials: CM
authors.lastname: Lehr
authors.forename: D
authors.initials: D
authors.lastname: Neumann
authors.forename: U F
authors.initials: UF
authors.lastname: Schaefer
authors.forename: G
authors.initials: G
authors.lastname: Wittum
mesh_terms: D002110:Caffeine / Q000378:metabolism / Q000493:pharmacokinetics*; D004058:Diffusion; D005260:Female; D005439:Flufenamic Acid / Q000378:metabolism / Q000493:pharmacokinetics*; D006801:Humans; D008954:Models, Biological; D012867:Skin / Q000378:metabolism*; D012869:Skin Absorption
chemical_list: D002110:Caffeine; D005439:Flufenamic Acid