{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T21:58:48Z","timestamp":1773179928770,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,5,11]],"date-time":"2021-05-11T00:00:00Z","timestamp":1620691200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["N\u00b0 813440 (ORBITAL\u2014Ocular Research by Integrated Training And Learning)"],"award-info":[{"award-number":["N\u00b0 813440 (ORBITAL\u2014Ocular Research by Integrated Training And Learning)"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UID\/QUI\/00100\/2019, UIDB\/00100\/2020, and UID\/BIM\/04585\/2020"],"award-info":[{"award-number":["UID\/QUI\/00100\/2019, UIDB\/00100\/2020, and UID\/BIM\/04585\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>The permeability through the cornea determines the ability of a drug or any topically applied compound to cross the tissue and reach the intraocular area. Most of the permeability values found in the literature are obtained considering topical drug formulations, and therefore, refer to the drug permeability inward the eye. However, due to the asymmetry of the corneal tissue, outward drug permeability constitutes a more meaningful parameter when dealing with intraocular drug-delivery systems (i.e., drug-loaded intraocular lenses, intraocular implants or injections). Herein, the permeability coefficients of two commonly administered anti-inflammatory drugs (i.e., bromfenac sodium and dexamethasone sodium) were determined ex vivo using Franz diffusion cells and porcine corneas in both inward and outward configurations. A significantly higher drug accumulation in the cornea was detected in the outward direction, which is consistent with the different characteristics of the corneal layers. Coherently, a higher permeability coefficient was obtained for bromfenac sodium in the outward direction, but no differences were detected for dexamethasone sodium in the two directions. Drug accumulation in the cornea can prolong the therapeutic effect of intraocular drug-release systems.<\/jats:p>","DOI":"10.3390\/pharmaceutics13050694","type":"journal-article","created":{"date-parts":[[2021,5,11]],"date-time":"2021-05-11T11:30:16Z","timestamp":1620732616000},"page":"694","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Asymmetry in Drug Permeability through the Cornea"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2321-906X","authenticated-orcid":false,"given":"Nadia","family":"Toffoletto","sequence":"first","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Instituto Superior T\u00e9cnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"},{"name":"Centro de Investiga\u00e7\u00e3o Interdisciplinar Egas Moniz, Instituto Universit\u00e1rio Egas Moniz, Quinta da Granja, Monte de Caparica, 2829-511 Caparica, Portugal"}]},{"given":"Anuj","family":"Chauhan","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Colorado School of Mines, Golden, CO 80401, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8546-7085","authenticated-orcid":false,"given":"Carmen","family":"Alvarez-Lorenzo","sequence":"additional","affiliation":[{"name":"Departamento de Farmacolog\u00eda, Farmacia y Tecnolog\u00eda Farmac\u00e9utica, I+D Farma (GI-1645), Facultad de Farmacia and Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain"}]},{"given":"Benilde","family":"Saramago","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Instituto Superior T\u00e9cnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6179-9296","authenticated-orcid":false,"given":"Ana Paula","family":"Serro","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Instituto Superior T\u00e9cnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"},{"name":"Centro de Investiga\u00e7\u00e3o Interdisciplinar Egas Moniz, Instituto Universit\u00e1rio Egas Moniz, Quinta da Granja, Monte de Caparica, 2829-511 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Bachu, R.D., Chowdhury, P., Al-Saedi, Z.H.F., Karla, P.K., and Boddu, S.H.S. (2018). Ocular drug delivery barriers\u2014Role of nanocarriers in the treatment of anterior segment ocular diseases. 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