{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:36:14Z","timestamp":1760236574305,"version":"build-2065373602"},"reference-count":67,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2021,12,6]],"date-time":"2021-12-06T00:00:00Z","timestamp":1638748800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Union","doi-asserted-by":"publisher","award":["610950"],"award-info":[{"award-number":["610950"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Free State of Thuringia, Germany","award":["2018 IZN 004"],"award-info":[{"award-number":["2018 IZN 004"]}]},{"name":"European Regional Development Fund; COMPETE2020; Portugal 2020","award":["POCI-01-0247-FEDER-045908","NORTE-01-0247-FEDER-046985"],"award-info":[{"award-number":["POCI-01-0247-FEDER-045908","NORTE-01-0247-FEDER-046985"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In a new era for digital health, dry electrodes for biopotential measurement enable the monitoring of essential vital functions outside of specialized healthcare centers. In this paper, a new type of nanostructured titanium-based thin film is proposed, revealing improved biopotential sensing performance and overcoming several of the limitations of conventional gel-based electrodes such as reusability, durability, biocompatibility, and comfort. The thin films were deposited on stainless steel (SS) discs and polyurethane (PU) substrates to be used as dry electrodes, for non-invasive monitoring of body surface biopotentials. Four different Ti\u2013Me (Me = Al, Cu, Ag, or Au) metallic binary systems were prepared by magnetron sputtering. The morphology of the resulting Ti\u2013Me systems was found to be dependent on the chemical composition of the films, specifically on the type and amount of Me. The existence of crystalline intermetallic phases or glassy amorphous structures also revealed a strong influence on the morphological features developed by the different systems. The electrodes were tested in an in-vivo study on 20 volunteers during sports activity, allowing study of the application-specific characteristics of the dry electrodes, based on Ti\u2013Me intermetallic thin films, and evaluation of the impact of the electrode\u2013skin impedance on biopotential sensing. The electrode\u2013skin impedance results support the reusability and the high degree of reliability of the Ti\u2013Me dry electrodes. The Ti\u2013Al films revealed the least performance as biopotential electrodes, while the Ti\u2013Au system provided excellent results very close to the Ag\/AgCl reference electrodes.<\/jats:p>","DOI":"10.3390\/s21238143","type":"journal-article","created":{"date-parts":[[2021,12,6]],"date-time":"2021-12-06T22:18:42Z","timestamp":1638829122000},"page":"8143","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Me-Doped Ti\u2013Me Intermetallic Thin Films Used for Dry Biopotential Electrodes: A Comparative Case Study"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8266-0111","authenticated-orcid":false,"given":"Cl\u00e1udia","family":"Lopes","sequence":"first","affiliation":[{"name":"Centro de F\u00edsica das Universidades do Minho e Porto, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9196-0717","authenticated-orcid":false,"given":"Patrique","family":"Fiedler","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering and Informatics, Technische Universit\u00e4t Ilmenau, 98693 Ilmenau, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3291-0925","authenticated-orcid":false,"given":"Marco Sampaio","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"Centro de F\u00edsica das Universidades do Minho e Porto, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7421-6902","authenticated-orcid":false,"given":"Joel","family":"Borges","sequence":"additional","affiliation":[{"name":"Centro de F\u00edsica das Universidades do Minho e Porto, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0972-9178","authenticated-orcid":false,"given":"Maurizio","family":"Bertollo","sequence":"additional","affiliation":[{"name":"Behavioral Imaging and Neural Dynamics Center, University \u201cG. d\u2019Annunzio\u201d of Chieti-Pescara, 66100 Chieti, Italy"},{"name":"Department of Medicine and Aging Sciences, University \u201cG. d\u2019Annunzio\u201d of Chieti-Pescara, 66100 Chieti, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0633-8937","authenticated-orcid":false,"given":"Eduardo","family":"Alves","sequence":"additional","affiliation":[{"name":"Instituto de Plasmas e Fus\u00e3o Nuclear, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"given":"Nuno Pessoa","family":"Barradas","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa EN10, 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8100-457X","authenticated-orcid":false,"given":"Silvia","family":"Comani","sequence":"additional","affiliation":[{"name":"Behavioral Imaging and Neural Dynamics Center, University \u201cG. d\u2019Annunzio\u201d of Chieti-Pescara, 66100 Chieti, Italy"},{"name":"Department of Neuroscience Imaging and Clinical Sciences, University \u201cG. d\u2019Annunzio\u201d of Chieti-Pescara, 66100 Chieti, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3871-2890","authenticated-orcid":false,"given":"Jens","family":"Haueisen","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering and Informatics, Technische Universit\u00e4t Ilmenau, 98693 Ilmenau, Germany"},{"name":"Department of Neurology, Biomagnetic Center, Jena University Hospital, 07747 Jena, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5506-996X","authenticated-orcid":false,"given":"Filipe","family":"Vaz","sequence":"additional","affiliation":[{"name":"Centro de F\u00edsica das Universidades do Minho e Porto, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1088\/0967-3334\/21\/2\/307","article-title":"A direct comparison of wet, dry and insulating bioelectric recording electrodes","volume":"21","author":"Searle","year":"2000","journal-title":"Physiol. 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