Colorimetric viral detection based on sialic acid stabilized gold nanoparticles

Sialic acid reduced and stabilized gold nanoparticles (d=20.1 +/- 1.8 nm) were synthesized by a simple one-pot, green method without chemically modifying sialic acid for colorimetric detection of influenza virus. The gold nanoparticles showed target-specific aggregation with viral particles via hemagglutininsialic acid binding. A linear correlation was observed between the change in optical density and dilution of chemically inactivated influenza B/Victoria and influenza B/Yamagata. Virus dilution (hemagglutination assay titer, 512) of 0.156 vol% was readily detected. The upper limit of the linearity can be extended with the use of more sialic acid-gold nanoparticles. (C) 2012 Elsevier B.V. All rights reserved: