Virus gene sensing detection method based on TiO2NR @ AgNPs chip and the multifunctional SERS microspheres

Surface-enhanced Raman spectroscopy (SERS) has rapidly emerged as a powerful and indispensable tool for the detection of trace viral gene targets in aqueous solutions. However, SERS performance is constrained by the focal area hotspot density and analyte concentration, impairing reproducibility for detection. This study unveils a novel SERS strategy, which synergistically integrates TiO₂NR @ AgNPs chips with multifunctional SERS microspheres. These multifunctional SERS microspheres enable the selective enrichment of target biomolecules within aqueous solutions. Moreover, the utilization of rubidium magnets to enrich and anchor these microspheres on the surface of TiO₂NR @ AgNPs chips results in the formation of stable and densely packed hotspots within the contact region. Ultimately, this strategy is applied for the immunocapture and detection of respiratory syncytial virus (RSV) genes within aqueous solutions. The computed results demonstrate that the SERS enhancement factors (EFs) achieved by this strategy is 1.14 × 10⁷. In particular, it achieves a detection limit for the RSV gene of <1 pM, underscoring its exceptional sensitivity. Thus, this strategy promises to advance the detection capabilities of viral genes in heterogeneous, complex, and dynamic biological aqueous solutions.