Detection of influenza virus by agglutination using nanoparticles conjugated with a sialic acid-mimic peptide

Influenza virus (IFV) detection in the early phase of disease is critical for effective anti-influenza therapy using neuraminidase inhibitors. Sialyloligosaccharide receptors on the surface of respiratory cells are recognized by IFV hemagglutinin (HA) in the infection. Here, we show that agglutination of IFV is detected using poly(glycidyl methacrylate) (PGMA)-coated polystyrene nanoparticles conjugated with a sialic acid-mimic peptide. The azido peptide was immobilized onto the surface of the PGMA-coated nanoparticles by click chemistry. The distribution of particle size, determined by dynamic light scattering, indicated that the peptide-conjugated nanoparticles were agglutinated in the presence of HA and IFV. Nanoparticles conjugated with the receptor-mimic peptide may be a useful alternative to red blood cells in the global surveillance and clinical diagnosis of influenza. This study examines the use of poly(glycidyl methacrylate) (PGMA)-coated polystyrene functionalized with peptides that mimic receptors found on red blood cells for detection of the influenza virus. Although the current method, the hemagglutination inhibition test, utilized by the World Health Organization, is simple, it has some limitations. We found that our peptide dimers attached to beads were efficiently agglutinated, leading us to detect the presence of the influenza virus antigens. We believe that our study makes a significant contribution to the fight against influenza because we provide an alternative method for the important task of influenza surveillance and diagnosis.