detection. Primary aptamers were attached to metal particles of a SERS substrate,
and influenza viruses were captured and bound with secondary aptamers labeled
with Raman-active molecules. Aptamer-based sensors provided recognition of various influenza viral strains, including H1, H3, and H5 hemagglutinin subtypes [38]
(see Fig. 1). SERS-based biosensors have been used increasingly over the past few
years, including an extremely highly sensitive methods [39].
Fig. 1 Design of aptasensor for influenza virus. (a) Scheme of sandwich-like aptasensor for IV
detection: (1) primary aptamer is immobilized onto Ag nanoparticles, (2) IV is captured with
primary aptamers, and (3) secondary aptamers interact with IV, providing the SERS signal. (b)
SEM image of the empty substrate. (c) AFM image of the control zone with adsorbed components
of allantoic fluid. (d) AFM image of the experimental zone with a dense layer of virus particles
adsorbed from the sample with 0.64 HAU/mL concentration (Figure from [38])
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