{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T02:13:45Z","timestamp":1773281625515,"version":"3.50.1"},"reference-count":23,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2014,5,16]],"date-time":"2014-05-16T00:00:00Z","timestamp":1400198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The cornea is a very particular tissue due to its transparency and its barrier function as it has to resist against the daily insults of the external environment. In addition, maintenance of this barrier function is of crucial importance to ensure a correct corneal homeostasis. Here, the corneal epithelial permeability has been assessed in vivo by means of non-invasive tetrapolar impedance measurements, taking advantage of the huge impact of the ion fluxes in the passive electrical properties of living tissues. This has been possible by using a flexible sensor based in SU-8 photoresist. In this work, a further analysis focused on the validation of the presented sensor is performed by monitoring the healing process of corneas that were previously wounded. The obtained impedance measurements have been compared with the damaged area observed in corneal fluorescein staining images. The successful results confirm the feasibility of this novel method, as it represents a more sensitive in vivo and non-invasive test to assess low alterations of the epithelial permeability. Then, it could be used as an excellent complement to the fluorescein staining image evaluation.<\/jats:p>","DOI":"10.3390\/s140508718","type":"journal-article","created":{"date-parts":[[2014,5,16]],"date-time":"2014-05-16T12:09:04Z","timestamp":1400242144000},"page":"8718-8727","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["New Trends in Quantitative Assessment of the Corneal  Barrier Function"],"prefix":"10.3390","volume":"14","author":[{"given":"Anton","family":"Guimer\u00e0","sequence":"first","affiliation":[{"name":"Institut de Microelectr\u00f2nica de Barcelona IMB-CNM (CSIC), 08193 Bellaterra, Spain"},{"name":"CIBER-BBN, Networking Center on Bioengineering, Biomaterials and Nanomedicine,  50018 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xavi","family":"Illa","sequence":"additional","affiliation":[{"name":"Institut de Microelectr\u00f2nica de Barcelona IMB-CNM (CSIC), 08193 Bellaterra, Spain"},{"name":"CIBER-BBN, Networking Center on Bioengineering, Biomaterials and Nanomedicine,  50018 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Estefania","family":"Traver","sequence":"additional","affiliation":[{"name":"Laboratorios SALVAT S.A., 08950 Esplugues de Llobregat, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carmen","family":"Herrero","sequence":"additional","affiliation":[{"name":"Laboratorios SALVAT S.A., 08950 Esplugues de Llobregat, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miguel","family":"Maldonado","sequence":"additional","affiliation":[{"name":"IOBA-Eye Institute, University of Valladolid, 47011 Valladolid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rosa","family":"Villa","sequence":"additional","affiliation":[{"name":"Institut de Microelectr\u00f2nica de Barcelona IMB-CNM (CSIC), 08193 Bellaterra, Spain"},{"name":"CIBER-BBN, Networking Center on Bioengineering, Biomaterials and Nanomedicine,  50018 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,5,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"639","DOI":"10.1016\/S1350-9462(01)00007-6","article-title":"Characteristics of the human ocular surface epithelium","volume":"20","author":"Kinoshita","year":"2001","journal-title":"Progr Retin Eye Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1016\/j.exer.2003.08.002","article-title":"Clinical responses of the corneal endothelium","volume":"78","author":"Bourne","year":"2004","journal-title":"Exp Eye Res."},{"key":"ref_3","first-page":"1830","article-title":"Measurement of corneal epithelial permeability to fluorescein. 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