{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,15]],"date-time":"2026-03-15T00:56:16Z","timestamp":1773536176150,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2020,6,28]],"date-time":"2020-06-28T00:00:00Z","timestamp":1593302400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["POCI-01-0145-FEDER-02861"],"award-info":[{"award-number":["POCI-01-0145-FEDER-02861"]}],"id":[{"id":"10.13039\/501100008530","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":["POCI-01-0145-FEDER-02861"],"award-info":[{"award-number":["POCI-01-0145-FEDER-02861"]}],"id":[{"id":"10.13039\/501100001871","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":["UIDB\/04539\/2020"],"award-info":[{"award-number":["UIDB\/04539\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011929","name":"Programa Operacional Tem\u00e1tico Factores de Competitividade","doi-asserted-by":"publisher","award":["POCI-01-0145-FEDER-02861"],"award-info":[{"award-number":["POCI-01-0145-FEDER-02861"]}],"id":[{"id":"10.13039\/501100011929","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>The intracranial measurement of local cerebral tissue oxygen levels\u2014PbtO2\u2014has become a useful tool for the critical care unit to investigate severe trauma and ischemia injury in patients. Our preliminary work in animal models supports the hypothesis that multi-site depth electrode recording of PbtO2 may give surgeons and critical care providers needed information about brain viability and the capacity for better recovery. Here, we present a surface morphology characterization and an electrochemical evaluation of the analytical properties toward oxygen detection of an FDA-approved, commercially available, clinical grade depth recording electrode comprising 12 Pt recording contacts. We found that the surface of the recording sites is composed of a thin film of smooth Pt and that the electrochemical behavior evaluated by cyclic voltammetry in acidic and neutral electrolyte is typical of polycrystalline Pt surface. The smoothness of the Pt surface was further corroborated by determination of the electrochemical active surface, confirming a roughness factor of 0.9. At an optimal working potential of \u22120.6 V vs. Ag\/AgCl, the sensor displayed suitable values of sensitivity and limit of detection for in vivo PbtO2 measurements. Based on the reported catalytical properties of Pt toward the electroreduction reaction of O2, we propose that these probes could be repurposed for multisite monitoring of PbtO2 in vivo in the human brain.<\/jats:p>","DOI":"10.3390\/mi11070632","type":"journal-article","created":{"date-parts":[[2020,6,29]],"date-time":"2020-06-29T05:28:56Z","timestamp":1593408536000},"page":"632","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Electrochemical Evaluation of a Multi-Site Clinical Depth Recording Electrode for Monitoring Cerebral Tissue Oxygen"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7737-4241","authenticated-orcid":false,"given":"Ana","family":"Ledo","sequence":"first","affiliation":[{"name":"Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal"},{"name":"Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8123-7007","authenticated-orcid":false,"given":"Eliana","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"}]},{"given":"Jorge E.","family":"Quintero","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Kentucky Medical Center, Lexington, KY 40536, USA"}]},{"given":"Greg A.","family":"Gerhardt","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Kentucky Medical Center, Lexington, KY 40536, USA"},{"name":"Department of Neuroscience, University of Kentucky Medical Center, Lexington, KY 40536, USA"}]},{"given":"Rui M.","family":"Barbosa","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal"},{"name":"Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1155\/2017\/6097265","article-title":"Brain Multimodality Monitoring: A New Tool in Neurocritical Care of Comatose Patients","volume":"2017","author":"Tasneem","year":"2017","journal-title":"Crit. 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