biostudies-literatureUnknown15(1)Eshaghi GFriedrich-Schiller-Universität JenaHere we report a novel platform for the detection of nucleocapsid (N) and receptor-binding domain (RBD) of spike (S) proteins of SARS-CoV-2 viruses using the surface plasmon resonance (SPR) technique. We demonstrate that the functionalization of SPR sensors with molecular 2D materials - 1 nm thick carbon nanomembranes (CNMs) significantly enhances sensitivity. CNMs terminated with azide linker (N3-CNM) enable covalent bonding of SARS-CoV-2 antibodies for specific immobilization of the N- and S-proteins to the sensor surface. The successful and stable hierarchical functionalization is confirmed by multiparametric SPR measurements complemented with X-ray photoelectron spectroscopy and polarization modulation infrared reflection absorption spectroscopy. The obtained equilibrium dissociation constants (KD) for the N-protein and the S-protein in the physiological buffer are 570 ± 50 pM and 22 ± 2 pM and the low detection limits (LODs) are ~ 190 pM and ~ 10 pM, respectively. The high specificity of the developed sensors is shown via their negligible cross-reactivity with SARS-CoV-1 and MERS-CoV proteins. Finally, detection of SARS-CoV-2 proteins in nasopharyngeal swab samples with the LOD of ~ 40 pM is demonstrated. The proposed methodology enables the development of biosensors that cover clinically relevant range for the direct and immediate detection of SARS-CoV-2 without any amplification or labeling.Scientific reports31248https://www.ebi.ac.uk/biostudies/studies/S-EPMC12378216biostudies-literatureHighly sensitive and label-free detection of SARS-CoV-2 proteins via surface plasmon resonance using biofunctionalization with 1 nm thick carbon nanomembranes.PMC12378216Neumann CGary DFischer TKaiser DFrey MEnnaciri RFrankenfeld KEshaghi GRasouli HRTurchanin AfalseHighly sensitive and label-free detection of SARS-CoV-2 proteins via surface plasmon resonance using biofunctionalization with 1 nm thick carbon nanomembranes.Here we report a novel platform for the detection of nucleocapsid (N) and receptor-binding domain (RBD) of spike (S) proteins of SARS-CoV-2 viruses using the surface plasmon resonance (SPR) technique. We demonstrate that the functionalization of SPR sensors with molecular 2D materials - 1 nm thick carbon nanomembranes (CNMs) significantly enhances sensitivity. CNMs terminated with azide linker (N3-CNM) enable covalent bonding of SARS-CoV-2 antibodies for specific immobilization of the N- and S-proteins to the sensor surface. The successful and stable hierarchical functionalization is confirmed by multiparametric SPR measurements complemented with X-ray photoelectron spectroscopy and polarization modulation infrared reflection absorption spectroscopy. The obtained equilibrium dissociation constants (KD) for the N-protein and the S-protein in the physiological buffer are 570 ± 50 pM and 22 ± 2 pM and the low detection limits (LODs) are ~ 190 pM and ~ 10 pM, respectively. The high specificity of the developed sensors is shown via their negligible cross-reactivity with SARS-CoV-1 and MERS-CoV proteins. Finally, detection of SARS-CoV-2 proteins in nasopharyngeal swab samples with the LOD of ~ 40 pM is demonstrated. The proposed methodology enables the development of biosensors that cover clinically relevant range for the direct and immediate detection of SARS-CoV-2 without any amplification or labeling.2025-01-01T00:00:00Z2025 Aug2026-05-10T04:22:22.515Z2026-04-08T01:29:25.329ZS-EPMC123782164085510710.1038/s41598-025-16342-5