Cardoso, Ana R.Suleimenova, A.Alves, João FredericoFrasco, Manuela F.Barquinha, PedroSales, M. Goreti F.2025-06-042025-06-042025-020026-265XPURE: 117540238PURE UUID: 89cf3f4a-2841-4f0c-b243-1a19ac270a7cScopus: 85214313269WOS: 001407027000001http://hdl.handle.net/10362/183867The authors acknowledge funding through project TecniCov (POCI-01-02B7-FEDER-069745), co-funded by FEDER through COMPETE2020 and Lisboa2020. ARC and JFA acknowledge funding from National Foundation for Science and Technology, I.P. (FCT), Portugal through the PhD grants, references (COVID/BD/15279/2022). This research is also funded by FEDER funds through COMPETE (Programa Operacional Factores de Competitividade) and national funds through Funda\u00E7\u00E3o para a Ci\u00EAncia e a Tecnologia, I.P. (FCT), in the scope of references UID/EMS/00285/2020 (CEMMPRE).The authors acknowledge Professor Hugo \u00C1guas (NOVA FCT) for the Raman Measurements. Publisher Copyright: © 2025 The AuthorsThis study presents a novel method for the fabrication of graphene as a functional interface for electrochemical sensors. Graphene was synthesized by probe-assisted ultrasonic exfoliation of graphite stabilized by the SARS-CoV-2 spike (S) protein. In this dual-function approach, the S protein is used for both graphene stabilization and antibody recognition, simplifying the production of biosensors. The biosensor was fabricated by modifying a carbon working electrode with the stabilized graphene-S-protein complex. Electrochemical impedance spectroscopy revealed a linear detection range from 1.0 pg/mL to 10.0 ng/mL in diluted human serum, with a detection limit of 0.17 pg/mL. The high selectivity for the S protein was confirmed against the SARS-CoV-2 nucleocapsid protein. The device successfully analysed serum samples, demonstrating its practical application. These results emphasize a simple, innovative platform that integrates graphene synthesis and biosensor functionality. This approach not only ensures a sensitive and stable substrate for monitoring antibodies against SARS-CoV-2, but also offers an approach that can be extended to detect different antibodies, by selecting the stabilizing protein that binds to the intended antibody.3466791engCarbon-working electrodeElectrochemical biosensorGraphenePoint-of-care testingSARS-CoV-2Spike proteinAnalytical ChemistrySpectroscopySDG 3 - Good Health and Well-beingjournal article10.1016/j.microc.2025.112647https://www.scopus.com/pages/publications/85214313269