{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T09:58:24Z","timestamp":1791367104853,"version":"4.3.1"},"reference-count":50,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:00:00Z","timestamp":1791331200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pharmacol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>\n                      Synthetic membranes and keratinocyte-based constructs are both used as accessible alternatives to\n                      <jats:italic>ex vivo<\/jats:italic>\n                      skin in\n                      <jats:italic>in vitro<\/jats:italic>\n                      permeation testing (IVPT), but they have not been compared directly for the same marketed products under identical conditions. This pilot study directly compared the synthetic Strat-M\u00ae membrane and a HaCaT construct under identical IVPT conditions using Voltaren\u00ae and Olfen\u00ae, two marketed, nominally dose-equivalent diclofenac gels. The aim was to determine whether the two barrier models yielded consistent apparent permeation parameters and led to the same comparative interpretation of the two formulations.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Permeation studies were performed using Franz diffusion cells in an internally controlled experimental design. Both formulations were tested in triplicate under identical conditions, including receptor medium, temperature, sampling protocol, and analytical method. Steady-state flux (Jss), permeability coefficient (Kp), lag time (\n                      <jats:italic>t<\/jats:italic>\n                      lag), and cumulative permeation profiles were determined and compared between barrier models.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Barrier model selection affected the apparent permeation behavior of diclofenac. Strat-M\u00ae detected a statistically significant difference in steady-state flux between Voltaren\u00ae and Olfen\u00ae, whereas no statistically significant between-formulation difference was detected with the HaCaT construct under the same experimental conditions. Lag time was the parameter most strongly influenced by barrier selection and was consistently shorter with the HaCaT construct than with Strat-M\u00ae.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>Under identical IVPT conditions, Strat-M\u00ae and the HaCaT-based epidermal construct generated different apparent permeation profiles and yielded different comparative assessments of Voltaren\u00ae and Olfen\u00ae. This model-dependent divergence underscores the need to justify barrier selection explicitly and to consider its limitations when interpreting comparative IVPT data.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphar.2026.1934405","type":"journal-article","created":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T09:43:35Z","timestamp":1791366215000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Barrier model selection alters apparent diclofenac permeation parameters: a controlled in vitro comparison of Strat-M\u00ae and a HaCaT-based epidermal construct"],"prefix":"10.3389","volume":"17","author":[{"given":"Filip","family":"Dugonik","sequence":"first","affiliation":[{"name":"Institute of Biomedical Sciences, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ur\u0161ka","family":"Jer\u0161i\u010d","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Sciences, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lejla","family":"Ka\u010d","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Sciences, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lidija","family":"Gradi\u0161nik","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Sciences, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tanja","family":"Zidari\u010d","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Sciences, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uro\u0161","family":"Maver","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Sciences, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]},{"name":"Department of Pharmacology, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tina","family":"Maver","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Sciences, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]},{"name":"Department of Pharmacology, Faculty of Medicine, University of Maribor","place":["Maribor, Slovenia"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,10,7]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"163","DOI":"10.2147\/CPAA.S64788","article-title":"Skin models for the testing of transdermal drugs","volume":"8","author":"Abd","year":"2016","journal-title":"Clin. 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