Target-size embracing dimension for sensitive detection of viruses with various sizes and influenza virus strains

The focused ion beam (FIB) technique was employed to precisely fabricate hexagon-like Au nano-rods (fibAu_h) arrays as a surface enhanced Raman scattering – active substrate. A “ring diameter” (DR) was created by the convergence of three fibAu_h with respect to the dimension of the target viruses (DT), such as adenovirus (Adeno), encephalomyocarditis virus (EMCV), influenza virus (H1N1) with different sizes. Three influenza A virus strains were also compared. The results indicate that as that with a DR/DT ratio of around 1, the discrimination ability for detecting the target viruses and SERS mechanism become obvious. The enhanced lightning rod effect surrounding the seized target virus is anticipated if its size and dimension is suitably embraced within three fibAu_h. Hence the as-designed fibAu_h sample with a target-size embracing dimension provides good discrimination ability for distinguishing virus of various sizes or virus strains.

► Hexagon-like Au nano-rods (fibAu_h) arrays were fabricated as SERS-active substrates.
► The ring diameter (DR) within 3 fibAu_h regarding the dimension of target virus (DT) was optimized.
► As the ratio DR/DT was nearly equal, the most intense SERS signal for target virus was found.
► The fibAu_h sample with an optimized DR was also competent to distinguish virus strains.