Dendritic Mesoporous SiO₂-Based SERS-Nanozyme-Mediated Immunochromatographic Detection of Foodborne Viruses with Enhanced Sensitivity across Multiple Scenarios

Detecting low-concentration foodborne viruses in complex samples has long posed a great challenge. Here, we propose a colorimetric enhancement-surface-enhanced Raman scattering (SERS) quantitative dual-mode immunochromatographic assay (ICA), characterized by high flexibility, sensitivity, and stability, which can rapidly and accurately detect viruses in various environments, including field, home, and clinical laboratory settings. A multifunctional SERS nanozyme tag (DSAIA) is customized using dendritic mesoporous SiO₂ as the core, which is densely loaded with AuIr catalytic particles and coated with a layer of highly active 35 nm Au nanoparticles on the exterior, thereby simultaneously achieving monodispersity, strong peroxidase activity, and a high density of efficient SERS hotspots. By incorporating antibody-modified DSAIA into the ICA platform, the established technology facilitates rapid dual-mode detection of two significant foodborne viruses, norovirus (NoV) and adenovirus (AdV). In the nanozyme catalytic mode (visual recognition), the detection limits for NoV and AdV reached 0.001 ng/mL and 10² PFU/mL, respectively; in the SERS mode (instrumental analysis), the technology enables precise quantitative analysis and further lowers the detection limits to 0.00014 ng/mL (NoV) and 11 PFU/mL (AdV). Furthermore, by testing 92 clinical stool samples, the practicality of the proposed assay was confirmed, underscoring its immense potential for real-time virus detection.