Fig. 4: Heat map summarizing the sensor signals obtained with the multiplexed plasmonic biosensor.

The color gradient correlates with the biosensor signal and the antigen concentration (i.e., darker colors represent higher viral loads). The position of each antibody: CH1 – anti-IBV; CH2 – anti-RSV; CH3 – anti-IAV, and CH4 – anti-COV. For each sample (n = 46), the data represent the mean of triplicate measurements (twice using the PDMS flow cell and once using the disposable microfluidic cartridge).