2026-05-08T18:40:46Zhttps://repisalud.isciii.es/rest/oai/request

oai:repisalud.isciii.es:20.500.12105/202782025-05-07T08:54:58Zcom_20.500.12105_19604com_20.500.12105_2051col_20.500.12105_19605

00925njm 22002777a 4500 dc Lozano-Chamizo, Laura author Márquez, Carlos author Marciello, Marzia author Galdon, José Carlos author de la Fuente-Zapico, Elsa author Martinez-Mazón, Paula author González-Rumayor, Víctor author Filice, Marco author Gamiz, Francisco author 2024-04-15 The COVID-19 pandemic has taught us valuable lessons, especially the urgent need for a widespread, rapid and sensitive diagnostic tool. To this, the integration of bidimensional nanomaterials, particularly graphene, into point-of-care biomedical devices is a groundbreaking strategy able to potentially revolutionize the diagnostic landscape. Despite advancements in the fabrication of these biosensors, the relationship between their surface biofunctionalization and sensing performance remains unclear. Here, we demonstrate that the combination of careful sensor fabrication and its precise surface biofunctionalization is crucial for exalting the sensing performances of 2D biosensors. Specifically, we have biofunctionalized Graphene Field-Effect Transistor (GFET) sensors surface through different biochemical reactions to promote either random/heterogeneous or oriented/homogeneous immobilization of the Anti-SARS-CoV-2 spike protein antibody. Each strategy was thoroughly characterized by in-silico simulations, physicochemical and biochemical techniques and electrical characterization. Subsequently, both biosensors were tested in the label-free direct titration of SARS-CoV-2 virus in simulated clinical samples, avoiding sample preprocessing and within short timeframes. Remarkably, the oriented GFET biosensor exhibited significantly enhanced reproducibility and responsiveness, surpassing the detection sensitivity of conventional non-oriented GFET by more than twofold. This breakthrough not only involves direct implications for COVID-19 surveillance and next pandemic preparedness but also clarify an unexplored mechanistic dimension of biosensor research utilizing 2D-nanomaterials. Biosens Bioelectron. 2024 Apr 15:250:116040. 10.1016/j.bios.2024.116040 1873-4235 Biosensors & bioelectronics 38290380 http://hdl.handle.net/20.500.12105/20278 High enhancement of sensitivity and reproducibility in label-free SARS-CoV-2 detection with graphene field-effect transistor sensors through precise surface biofunctionalization control.