Fig. 5: Colorimetric detection of I223R/H275Y pH1N1 using A4.

a Optical images of A4-Au NPs in the presence of I223R/H275Y pH1N1 (upper panel) and wt pH1N1 (lower panel). Each experiment was repeated three times independently with similar results. b Plot of Abs580/Abs520 versus the number of influenza virus. Data represent the average plus/minus standard deviation from three measurements.