{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:29:43Z","timestamp":1760236183364,"version":"build-2065373602"},"reference-count":53,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,11,5]],"date-time":"2021-11-05T00:00:00Z","timestamp":1636070400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/QUI-COL\/30834\/2017","CEECIND\/01620\/2017"],"award-info":[{"award-number":["PTDC\/QUI-COL\/30834\/2017","CEECIND\/01620\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["MPs"],"abstract":"<jats:p>Stratum corneum (SC) represents the outermost layer of the skin, being an effective barrier against the entry of molecules and pathogens. Skin research has given particular focus to SC as it hampers effective drug delivery for cosmetical and therapeutical purposes. Following recommendations to develop alternative models to animals, the SC isolated from skin obtained from medical procedures or from pigs has gained extensive attention. Yet, there is still missing a standard and simple procedure accepted within the scientific community to avoid application of different isolated SC methodologies, a fact that may hamper progress in skin research. Considering this challenge, the present study evaluated different experimental conditions aiming to establish a useful and sustainable solvent-free procedure for the obtention of a realistic SC model. The studied trypsin digestion parameters included concentration, incubation period and temperature. Isolated SC was characterized using histological analysis and calcein\u2019s permeability, after the procedure and during a 6-week storage period. Data recommend trypsin digestion at 4 \u00b0C for 20 h as the most effective procedure to isolate SC from pig ear skin. This work contributes to standardize the SC isolation procedure, and to obtain a valuable and reliable SC mimetic model for skin drug development.<\/jats:p>","DOI":"10.3390\/mps4040080","type":"journal-article","created":{"date-parts":[[2021,11,7]],"date-time":"2021-11-07T20:42:54Z","timestamp":1636317774000},"page":"80","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Protocol for the Isolation of Stratum Corneum from Pig Ear Skin: Evaluation of the Trypsin Digestion Conditions"],"prefix":"10.3390","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3175-3844","authenticated-orcid":false,"given":"T\u00e2nia","family":"Moniz","sequence":"first","affiliation":[{"name":"LAQV, REQUIMTE, Departamento de Ci\u00eancias Qu\u00edmicas, Faculdade de Farm\u00e1cia, Universidade do Porto, Portugal, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8777-5877","authenticated-orcid":false,"given":"Sofia A. Costa","family":"Lima","sequence":"additional","affiliation":[{"name":"LAQV, REQUIMTE, Departamento de Ci\u00eancias Qu\u00edmicas, Faculdade de Farm\u00e1cia, Universidade do Porto, Portugal, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0736-2835","authenticated-orcid":false,"given":"Salette","family":"Reis","sequence":"additional","affiliation":[{"name":"LAQV, REQUIMTE, Departamento de Ci\u00eancias Qu\u00edmicas, Faculdade de Farm\u00e1cia, Universidade do Porto, Portugal, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4314","DOI":"10.1111\/bph.15184","article-title":"Human skin models: From healthy to disease-mimetic systems; characteristics and applications","volume":"177","author":"Moniz","year":"2020","journal-title":"Br. J. 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