{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,12]],"date-time":"2026-09-12T19:03:42Z","timestamp":1789239822879,"version":"build-2803163510"},"reference-count":38,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,9]],"date-time":"2025-01-09T00:00:00Z","timestamp":1736380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Map Your DNA Ltd.","award":["23\/07\/2020\/UD"],"award-info":[{"award-number":["23\/07\/2020\/UD"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Biosensors are transforming point-of-care diagnostics by simplifying the detection process and enabling rapid, accurate testing. This study introduces a novel, reusable biosensor designed for direct viral RNA detection from unfiltered saliva, targeting SARS-CoV-2. Unlike conventional methods requiring filtration, our biosensor leverages a unique electrode design that prevents interference from saliva debris, allowing precise measurements. The biosensor is based on electrochemical principles, employing oligonucleotide probes immobilized on a hydrophobic-coated electrode, which prevents air bubbles and salt crystal formation. During validation, the biosensor demonstrated a sensitivity and specificity of 100%, accurately identifying SARS-CoV-2 in saliva samples without false positives or negatives. Cross-validation with RT-qPCR, the gold standard for COVID-19 diagnostics, confirmed the reliability of our device. The biosensor\u2019s performance was tested on 60 participants, yielding 12 true positive results and 48 true negatives, aligning perfectly with RT-qPCR outcomes. This reusable, easy-to-use biosensor offers significant potential for point-of-care applications in various healthcare settings, providing a fast, efficient, and cost-effective method for detecting viral infections such as COVID-19. Its robust design, minimal sample preparation requirements, and multiple-use capability mark a significant advancement in biosensing technology.<\/jats:p>","DOI":"10.3390\/s25020360","type":"journal-article","created":{"date-parts":[[2025,1,9]],"date-time":"2025-01-09T09:54:27Z","timestamp":1736416467000},"page":"360","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Reusable Biosensor for Easy RNA Detection from Unfiltered Saliva"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8612-727X","authenticated-orcid":false,"given":"Pawe\u0142","family":"Wityk","sequence":"first","affiliation":[{"name":"Map Your DNA Ltd., \u015awierkowa 40, 83-330 Lniska, Poland"},{"name":"Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA"},{"name":"Department of Biopharmaceutics and Pharmacodynamics, Medical University of Gda\u0144sk, Al. Gen. J. Halera 107, 80-416 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8197-2885","authenticated-orcid":false,"given":"Agata","family":"Terebieniec","sequence":"additional","affiliation":[{"name":"Fungal Physiology, Westerdijk Fungal Biodiversity Institute and Fungal Molecular Physiology, Utrecht University, 3584 CS Utrecht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3037-644X","authenticated-orcid":false,"given":"Robert","family":"Nowak","sequence":"additional","affiliation":[{"name":"Institute of Physical Culture Sciences, University of Szczecin, 40B Piast\u00f3w Al., Building 6, 71-065 Szczecin, Poland"},{"name":"Department of Pathology, Pomeranian Medical University in Szczecin, 1 Unii Lubelskiej St., 71-242 Szczecin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0852-8400","authenticated-orcid":false,"given":"Jacek","family":"\u0141ubi\u0144ski","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering and Ship Technology, Gda\u0144sk University of Technology, Narutowicza 11\/12, 80-233 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6476-7580","authenticated-orcid":false,"given":"Martyna","family":"Mroczy\u0144ska-Szel\u0105g","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry, Gda\u0144sk University of Technology, Narutowicza 11\/12, 80-233 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomasz","family":"Wityk","sequence":"additional","affiliation":[{"name":"Map Your DNA Ltd., \u015awierkowa 40, 83-330 Lniska, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7025-3087","authenticated-orcid":false,"given":"Dorota","family":"Kostrzewa-Nowak","sequence":"additional","affiliation":[{"name":"Department of Clinical and Molecular Biochemistry, Pomeranian Medical University in Szczecin, 72 Powsta\u0144c\u00f3w Wlkp. 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