Figure 2From: Advanced biosensors for detection of pathogens related to livestock and poultryCartoon adapted from [42]. Colorimetric sensor for detection of influenza A virus. Sialic-mediated colorimetric detection of Influenza virus. Gold nanoparticles are stabilized with sialic to specifically bind HA protein on Influenza virus surface. Sialic-acid gold nanoparticles alone show the absorbance at 510 nm, while virus-bound nanoparticles absorbed at 600–610 nm. This allows label-free colorimetric readout for virus detection.Back to article page