Universal and highly sensitive detection of influenza A virus and streptococcus pneumoniae using WGA-modified magnetic SERS nanotags-based lateral flow assay.

Infection with influenza A (FluA) virus usually leads to secondary infection with streptococcus pneumoniae (s. pneumoniae). It is urgent to develop rapid, highly sensitive, simultaneous and universal point-of-care testing (POCT) techniques for FluA and s. pneumoniae. We developed a two-channel surface-enhanced Raman scattering (SERS)-lateral flow assay (LFA) technique based on wheat germ agglutinin (WGA)-modified magnetic SERS nanotags (Fe3O4@Au-WGA), for detection of FluA and s. pneumoniae. The detection limits were 14 copies/mL for FluA and 10 cells/mL for s. pneumoniae, and the sensitivity was about 100 times higher than the visual signals. It was used to detect 80 FluA and s. pneumoniae positive throat swabs/sputum samples and 30 negative samples, with a diagnostic accuracy of 100 %, which was 19 % higher than that of commercial colloidal gold-LFA strips. Therefore, the proposed platform has a strong clinical application potential in the rapid, accurate, highly sensitive and universal detection of FluA and s. pneumoniae.