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Wang J, Nitsche JM, Kasting GB, Wittum G, Nägel A. Transdermal and lateral effective diffusivities for drug transport in stratum corneum from a microscopic anisotropic diffusion model. Eur J Pharm Biopharm 2023:S0939-6411(23)00032-2. [PMID: 36764498 DOI: 10.1016/j.ejpb.2023.01.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 10/10/2022] [Accepted: 01/27/2023] [Indexed: 02/11/2023]
Abstract
This paper presents a computational model of molecular diffusion through the interfollicular stratum corneum. Specifically, it extends an earlier two-dimensional microscopic model for the permeability in two ways: (1) a microporous leakage pathway through the intercellular lipid lamellae allows slow permeation of highly hydrophilic permeants through the tissue; and (2) the model yields explicit predictions of both lateral (D‾‖sc) and transdermal (D‾⊥sc) effective (average, homogenized) diffusivities of solutes within the tissue. We present here the mathematical framework for the analysis and a comparison of the predictions with experimental data on desorption of both hydrophilic and lipophilic solutes from human stratum corneum in vitro. Diffusion in the lipid lamellae is found to make the effective diffusivity highly anisotropic, with the predicted ratio D‾‖sc/D‾⊥sc ranging from 34-39 for fully hydrated skin and 150 to more than 1000 for partially hydrated skin. The diffusivities and their ratio are in accord with both experimental data and the results of mathematical analyses performed by others.
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Affiliation(s)
- Junxi Wang
- Goethe Center for Scientific Computing, Kettenhofweg 139, Goethe University, 60325 Frankfurt a.M., Germany
| | - Johannes M Nitsche
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260-4200, USA
| | - Gerald B Kasting
- James L. Winkle College of Pharmacy, University of Cincinnati Academic Health Center, Cincinnati, OH 45267-0514, USA
| | - Gabriel Wittum
- Goethe Center for Scientific Computing, Kettenhofweg 139, Goethe University, 60325 Frankfurt a.M., Germany; King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi-Arabia
| | - Arne Nägel
- Goethe Center for Scientific Computing, Kettenhofweg 139, Goethe University, 60325 Frankfurt a.M., Germany.
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Nitsche JM, Kasting GB. A Framework for Incorporating Transient Solute-Keratin Binding Into Dermal Absorption Models. J Pharm Sci 2022; 111:2093-2106. [DOI: 10.1016/j.xphs.2021.11.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 12/28/2022]
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Defraeye T, Bahrami F, Rossi RM. Inverse Mechanistic Modeling of Transdermal Drug Delivery for Fast Identification of Optimal Model Parameters. Front Pharmacol 2021; 12:641111. [PMID: 33995047 PMCID: PMC8117338 DOI: 10.3389/fphar.2021.641111] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 02/18/2021] [Indexed: 11/13/2022] Open
Abstract
Transdermal drug delivery systems are a key technology to administer drugs with a high first-pass effect in a non-invasive and controlled way. Physics-based modeling and simulation are on their way to become a cornerstone in the engineering of these healthcare devices since it provides a unique complementarity to experimental data and additional insights. Simulations enable to virtually probe the drug transport inside the skin at each point in time and space. However, the tedious experimental or numerical determination of material properties currently forms a bottleneck in the modeling workflow. We show that multiparameter inverse modeling to determine the drug diffusion and partition coefficients is a fast and reliable alternative. We demonstrate this strategy for transdermal delivery of fentanyl. We found that inverse modeling reduced the normalized root mean square deviation of the measured drug uptake flux from 26 to 9%, when compared to the experimental measurement of all skin properties. We found that this improved agreement with experiments was only possible if the diffusion in the reservoir holding the drug was smaller than the experimentally measured diffusion coefficients suggested. For indirect inverse modeling, which systematically explores the entire parametric space, 30,000 simulations were required. By relying on direct inverse modeling, we reduced the number of simulations to be performed to only 300, so a factor 100 difference. The modeling approach's added value is that it can be calibrated once in-silico for all model parameters simultaneously by solely relying on a single measurement of the drug uptake flux evolution over time. We showed that this calibrated model could accurately be used to simulate transdermal patches with other drug doses. We showed that inverse modeling is a fast way to build up an accurate mechanistic model for drug delivery. This strategy opens the door to clinically ready therapy that is tailored to patients.
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Affiliation(s)
- Thijs Defraeye
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, St. Gallen, Switzerland
| | - Flora Bahrami
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, St. Gallen, Switzerland.,University of Bern, ARTORG Center for Biomedical Engineering Research, Bern, Switzerland
| | - René M Rossi
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, St. Gallen, Switzerland
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Defraeye T, Bahrami F, Ding L, Malini RI, Terrier A, Rossi RM. Predicting Transdermal Fentanyl Delivery Using Mechanistic Simulations for Tailored Therapy. Front Pharmacol 2020; 11:585393. [PMID: 33117179 PMCID: PMC7550783 DOI: 10.3389/fphar.2020.585393] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 08/31/2020] [Indexed: 01/05/2023] Open
Abstract
Transdermal drug delivery is a key technology for administering drugs. However, most devices are “one-size-fits-all”, even though drug diffusion through the skin varies significantly from person-to-person. For next-generation devices, personalization for optimal drug release would benefit from an augmented insight into the drug release and percutaneous uptake kinetics. Our objective was to quantify the changes in transdermal fentanyl uptake with regards to the patient’s age and the anatomical location where the patch was placed. We also explored to which extent the drug flux from the patch could be altered by miniaturizing the contact surface area of the patch reservoir with the skin. To this end, we used validated mechanistic modeling of fentanyl diffusion, storage, and partitioning in the epidermis to quantify drug release from the patch and the uptake within the skin. A superior spatiotemporal resolution compared to experimental methods enabled in-silico identification of peak concentrations and fluxes, and the amount of stored drug and bioavailability. The patients’ drug uptake showed a 36% difference between different anatomical locations after 72 h, but there was a strong interpatient variability. With aging, the drug uptake from the transdermal patch became slower and less potent. A 70-year-old patient received 26% less drug over the 72-h application period, compared to an 18-year-old patient. Additionally, a novel concept of using micron-sized drug reservoirs was explored in silico. These reservoirs induced a much higher local flux (µg cm-2 h-1) than conventional patches. Up to a 200-fold increase in the drug flux was obtained from these small reservoirs. This effect was mainly caused by transverse diffusion in the stratum corneum, which is not relevant for much larger conventional patches. These micron-sized drug reservoirs open new ways to individualize reservoir design and thus transdermal therapy. Such computer-aided engineering tools also have great potential for in-silico design and precise control of drug delivery systems. Here, the validated mechanistic models can serve as a key building block for developing digital twins for transdermal drug delivery systems.
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Affiliation(s)
- Thijs Defraeye
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, St. Gallen, Switzerland
| | - Flora Bahrami
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, St. Gallen, Switzerland.,ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland
| | - Lu Ding
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, St. Gallen, Switzerland.,Laboratory of Biomechanical Orthopedics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Riccardo Innocenti Malini
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, St. Gallen, Switzerland
| | - Alexandre Terrier
- Laboratory of Biomechanical Orthopedics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - René M Rossi
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, St. Gallen, Switzerland
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Fujii MY, Asakawa Y, Fukami T. Potential application of novel liquid crystal nanoparticles of isostearyl glyceryl ether for transdermal delivery of 4-biphenyl acetic acid. Int J Pharm 2020; 575:118935. [PMID: 31816353 DOI: 10.1016/j.ijpharm.2019.118935] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 11/14/2019] [Accepted: 12/02/2019] [Indexed: 11/19/2022]
Abstract
Novel liquid crystal nanoparticles (LCNs) composed of isostearyl glyceryl ether (GE-IS) and ethoxylated hydrogenated castor oil (HCO-60) were developed for the enhanced transdermal delivery of 4-biphenyl acetic acid (BAA). The physical properties and pharmaceutical properties of the LCNs were measured. The interaction between the intercellular lipid model of the stratum corneum and the LCNs was observed to elucidate the skin permeation mechanism. In the formulation, the LCNs form niosomes with mean particles sizes of 180-300 nm. The skin absorption mechanisms of LCNs are different, depending upon the application and buffer concentration. The LCNs composed of GE-IS and HCO-60 are attractive tools for use as transdermal drug delivery systems carriers for medicines and cosmetics, due to their high efficiency and safety.
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Affiliation(s)
- Mika Yoshimura Fujii
- Department of Molecular Pharmaceutics, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588 Japan
| | - Yoko Asakawa
- Department of Molecular Pharmaceutics, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588 Japan
| | - Toshiro Fukami
- Department of Molecular Pharmaceutics, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588 Japan.
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Akl MA, Hady MA, Sayed OM. Buccal mucosal accumulation of dapoxetine using supersaturation, co-solvent and permeation enhancing polymer strategy. J Drug Deliv Sci Technol 2020. [DOI: 10.1016/j.jddst.2019.101411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Hewitt NJ, Grégoire S, Cubberley R, Duplan H, Eilstein J, Ellison C, Lester C, Fabian E, Fernandez J, Géniès C, Jacques-Jamin C, Klaric M, Rothe H, Sorrell I, Lange D, Schepky A. Measurement of the penetration of 56 cosmetic relevant chemicals into and through human skin using a standardized protocol. J Appl Toxicol 2019; 40:403-415. [PMID: 31867769 PMCID: PMC7027575 DOI: 10.1002/jat.3913] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 09/30/2019] [Accepted: 09/30/2019] [Indexed: 11/09/2022]
Abstract
OECD test guideline 428 compliant protocol using human skin was used to test the penetration of 56 cosmetic‐relevant chemicals. The penetration of finite doses (10 μL/cm2) of chemicals was measured over 24 hours. The dermal delivery (DD) (amount in the epidermis, dermis and receptor fluid [RF]) ranged between 0.03 ± 0.02 and 72.61 ± 8.89 μg/cm2. The DD of seven chemicals was comparable with in vivo values. The DD was mainly accounted for by the amount in the RF, although there were some exceptions, particularly of low DD chemicals. While there was some variability due to cell outliers and donor variation, the overall reproducibility was very good. As six chemicals had to be applied in 100% ethanol due to low aqueous solubility, we compared the penetration of four chemicals with similar physicochemical properties applied in ethanol and phosphate‐buffered saline. Of these, the DD of hydrocortisone was the same in both solvents, while the DD of propylparaben, geraniol and benzophenone was lower in ethanol. Some chemicals displayed an infinite dose kinetic profile; whereas, the cumulative absorption of others into the RF reflected the finite dosing profile, possibly due to chemical volatility, total absorption, chemical precipitation through vehicle evaporation or protein binding (or a combination of these). These investigations provide a substantial and consistent set of skin penetration data that can help improve the understanding of skin penetration, as well as improve the prediction capacity of in silico skin penetration models. The penetration of 56 chemicals was tested in human skin using a standard protocol. Dermal delivery correlated with the amount in the receptor fluid (RF). The impact of solvent on penetration was evaluated. Despite finite doses being applied, different profiles of cumulative absorption kinetics into the RF were observed. These data may help understand skin penetration and improve the prediction capacity of in silico skin penetration models.
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Affiliation(s)
| | | | | | | | - Joan Eilstein
- L'Oreal Research and Innovation, Aulnay-Sous-Bois, France
| | | | - Cathy Lester
- The Procter and Gamble Company, Cincinnati, Ohio
| | | | | | | | | | | | - Helga Rothe
- Procter and Gamble (currently Coty), Darmstadt, Germany
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Grégoire S, Cubberley R, Duplan H, Eilstein J, Lange D, Hewitt N, Jacques-Jamin C, Klaric M, Rothe H, Ellison C, Vaillant O, Schepky A. Solvent Solubility Testing of Cosmetics-Relevant Chemicals: Methodology and Correlation of Water Solubility to In Silico Predictions. J SOLUTION CHEM 2017. [DOI: 10.1007/s10953-017-0652-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Rush AK, Miller MA, Smith ED, Kasting GB. A quantitative radioluminographic imaging method for evaluating lateral diffusion rates in skin. J Control Release 2015; 216:1-8. [DOI: 10.1016/j.jconrel.2015.07.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 07/29/2015] [Accepted: 07/30/2015] [Indexed: 11/28/2022]
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Selzer D, Neumann D, Schaefer UF. Mathematical models for dermal drug absorption. Expert Opin Drug Metab Toxicol 2015; 11:1567-83. [PMID: 26166490 DOI: 10.1517/17425255.2015.1063615] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Mathematical models of dermal transport offer the advantages of being much faster and less expensive than in vitro or in vivo studies. The number of methods used to create such models has been increasing rapidly, probably due to the steady rise in computational power. Although each of the various approaches has its own virtues and limitations, it may be difficult to decide which approach is best suited to address a given problem. AREAS COVERED Here we outline the basic ideas, drawbacks and advantages of compartmental and quantitative structure-activity relationship models, as well as of analytical and numerical approaches for solving the diffusion equation. Examples of special applications of the different approaches are given. EXPERT OPINION Although some models are sophisticated and might be used in future to predict transport through damaged or diseased skin, the comparatively low availability of suitable and accurate experimental data limits extensive usage of these models and their predictive accuracy. Due to the lack of experimental data, the possibility of validating mathematical models is limited.
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Affiliation(s)
- Dominik Selzer
- a 1 Saarland University, Biopharmaceutics and Pharmaceutical Technology , 66123 Saarbruecken, Germany.,b 2 Scientific Consilience GmbH, Saarland University , Bldg. 30, 66123 Saarbruecken, Germany +49 681 302 71230 ; +49 681 302 64956 ;
| | - Dirk Neumann
- a 1 Saarland University, Biopharmaceutics and Pharmaceutical Technology , 66123 Saarbruecken, Germany.,b 2 Scientific Consilience GmbH, Saarland University , Bldg. 30, 66123 Saarbruecken, Germany +49 681 302 71230 ; +49 681 302 64956 ;
| | - Ulrich F Schaefer
- c 3 Saarland University, Biopharmaceutics and Pharmaceutical Technology , 66123 Saarbruecken, Germany
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A strategy for in-silico prediction of skin absorption in man. Eur J Pharm Biopharm 2015; 95:68-76. [PMID: 26022643 DOI: 10.1016/j.ejpb.2015.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 03/09/2015] [Accepted: 05/06/2015] [Indexed: 11/21/2022]
Abstract
For some time, in-silico models to address substance transport into and through the skin are gaining more and more importance in different fields of science and industry. In particular, the mathematical prediction of in-vivo skin absorption is of great interest to overcome ethical and economical issues. The presented work outlines a strategy to address this problem and in particular, investigates in-vitro and in-vivo skin penetration experiments of the model compound flufenamic acid solved in an ointment by means of a mathematical model. Experimental stratum corneum concentration-depth profiles (SC-CDP) for various time intervals using two different in-vitro systems (Franz diffusion cell, Saarbruecken penetration model) were examined and simulated with the help of a highly optimized three compartment numerical diffusion model and compared to the findings of SC-CDPs of the in-vivo scenario. Fitted model input parameters (diffusion coefficient and partition coefficient with respect to the stratum corneum) for the in-vitro infinite dose case could be used to predict the in-use conditions in-vitro. Despite apparent differences in calculated partition coefficients between in-vivo and in-vitro studies, prediction of in-vivo scenarios from input parameters calculated from the in-vitro case yielded reasonable results.
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In Silico Prediction of Percutaneous Absorption and Disposition Kinetics of Chemicals. Pharm Res 2014; 32:1779-93. [DOI: 10.1007/s11095-014-1575-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 11/10/2014] [Indexed: 11/26/2022]
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13
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Grassi M, Grassi G. Application of mathematical modeling in sustained release delivery systems. Expert Opin Drug Deliv 2014; 11:1299-321. [PMID: 24938598 DOI: 10.1517/17425247.2014.924497] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION This review, presenting as starting point the concept of the mathematical modeling, is aimed at the physical and mathematical description of the most important mechanisms regulating drug delivery from matrix systems. The precise knowledge of the delivery mechanisms allows us to set up powerful mathematical models which, in turn, are essential for the design and optimization of appropriate drug delivery systems. AREAS COVERED The fundamental mechanisms for drug delivery from matrices are represented by drug diffusion, matrix swelling, matrix erosion, drug dissolution with possible recrystallization (e.g., as in the case of amorphous and nanocrystalline drugs), initial drug distribution inside the matrix, matrix geometry, matrix size distribution (in the case of spherical matrices of different diameter) and osmotic pressure. Depending on matrix characteristics, the above-reported variables may play a different role in drug delivery; thus the mathematical model needs to be built solely on the most relevant mechanisms of the particular matrix considered. EXPERT OPINION Despite the somewhat diffident behavior of the industrial world, in the light of the most recent findings, we believe that mathematical modeling may have a tremendous potential impact in the pharmaceutical field. We do believe that mathematical modeling will be more and more important in the future especially in the light of the rapid advent of personalized medicine, a novel therapeutic approach intended to treat each single patient instead of the 'average' patient.
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Affiliation(s)
- Mario Grassi
- University of Trieste, Department of Engineering and Architecture , Via Valerio 6/A, I - 34127, Trieste , Italy +39 040 558 3435 ; +39 040 569823 ;
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Zhang Q, Saad P, Mao G, Walters RM, Mack Correa MC, Mendelsohn R, Flach CR. Infrared spectroscopic imaging tracks lateral distribution in human stratum corneum. Pharm Res 2014; 31:2762-73. [PMID: 24792828 DOI: 10.1007/s11095-014-1373-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 03/21/2014] [Indexed: 10/25/2022]
Abstract
PURPOSE To demonstrate the efficacy of infrared (IR) spectroscopic imaging for evaluation of lateral diffusion in stratum corneum (SC) and for elucidation of intermolecular interactions between exogenous agents and SC constituents. METHODS In separate experiments, acyl chain perdeuterated oleic acid (OA-d) and deuterated dimethyl sulfoxide (DMSO-d) were applied to the surface of isolated human SC. The lateral distribution of permeant concentrations was monitored using the time-dependence of IR images. Diffusion coefficients (D) were estimated from Fick's second law. Interactions between the exogenous agents and the SC were tracked from changes in CD2 and Amide I stretching frequencies. RESULTS Networked glyphs served as the major pathway for lateral distribution of OA-d. In glyph-poor regions, D values from 0.3-1 × 10(-8) cm(2)/s bracketed the OA-d data and apparently decreased with time. Although diffusion of DMSO-d is relatively fast compared to our experimental measurement time, the results suggest values of ~10(-7) cm(2)/s. OA-d spectral changes suggest penetration into the ordered lipids of the SC; DMSO-d penetration results in perturbation of SC keratin structure. CONCLUSIONS IR imaging provides concentration profiles, diffusion coefficients, and unique molecular level information about structural changes in the endogenous SC constituents and exogenous agents upon their mutual interaction. Transport along glyphs is the dominant mode of distribution for OA-d.
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Affiliation(s)
- Qihong Zhang
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey, 07102, USA
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Windbergs M, Hansen S, Schroeter A, Schaefer U, Lehr CM, Bouwstra J. From the Structure of the Skin Barrier and Dermal Formulations to in vitro Transport Models for Skin Absorption: Skin Research in the Netherlands and in Germany. Skin Pharmacol Physiol 2013; 26:317-30. [DOI: 10.1159/000351936] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 03/03/2013] [Indexed: 11/19/2022]
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