Extrinsic surface-enhanced Raman scattering detection of influenza A virus enhanced by two-dimensional gold@silver core–shell nanoparticle arrays

Abstract

A surface enhanced Raman scattering (SERS) based biosensor using a direct immunoassay platform was demonstrated for influenza A detection. The sensitivity was improved ~4 times by using a well-tuned Au@Ag 2D array instead of a flat Au film.

SERS-based immunoassay on 2D-arrays of Au@Ag core–shell nanoparticles: influence of the sizes of the SERS probe and sandwich immunocomplex on the sensitivity

“…Surface-enhanced Raman scattering (SERS)-based immunoassay has attracted much attention as an ultrasensitive detection method for analytes in biological samples. [1][2][3][4] The extrinsic SERS immunoassay is the platform for detecting target antigens using metal nanoparticles (MNPs), such as gold nanoparticles (AuNPs), 5 gold nanostars, 2 and their aggregates, 6 labelled with a Raman reporter molecule and the detection antibody, which are called 'SERS probes'. 7 The Raman scattering efficiency of the reporter molecule is signicantly enhanced by the strong electromagnetic eld near the MNP surface when the localized surface plasmon is excited by the incident laser light.…”

“…The sensitivity can be improved further by performing the immunoassay on SERS-active substrates, such as two-dimensional (2D) arrays of gold nanotriangle, 2 gold nanostar, 11 gold nanosphere, 12 and gold core-silver shell (Au@Ag) nanoparticles (NPs) 4 formed on solid substrates. Many research groups reported a variety of combinations of the SERS probe and SERS-active substrate, demonstrating the ultrasensitive detection of analytes.…”

“…Many research groups reported a variety of combinations of the SERS probe and SERS-active substrate, demonstrating the ultrasensitive detection of analytes. 3,4,13 This sensitivity improvement comes from the plasmon coupling between the SERS probe and the SERS-active substrate, whose strength becomes strong as the separation distance decreases. In sandwich SERS immunoassay, the capture-antibody/ antigen/detection-antibody complex (sandwich immunocomplexes) certainly acts as the separation barrier between the SERS probe and the SERS-active substrate.…”

Nanomaterial-based biosensors for detection of pathogenic virus

“…In another study two-dimensional (2D) coreeshell structure of (Au@Ag) NPs arrays was used as substrate for SERS based biosensor [64]. In this report, the target molecule was influenza A virus, being obtained a LOD of 6 TCID50/mL and a linear range between 5 and 56 TCID50/mL using a unique SERS substrate (well-tuned Au@Ag 2D array) ( Fig.…”

“…Design of a modified electrode with two-dimensional (2D) coreeshell structure of (Au@Ag) NPs array as substrate. This figure was obtained with permission from Ref [64]…”