Fig. 2.

A) ELISA response for two different PAb anti-SARS-CoV-2 1 μg/mL (Sinobiological and ProSci) towards two different Spike proteins coated at 2 ng/mL. B) Binding curve of colorimetric ELISA for MAb anti-SARS-CoV-2 ranging from 0.12 – 2 μg/mL. Coating of Spike protein: 2 ng/mL. C) Electrochemical response using the MBs-based assay using CB-based modified electrode (blue line) and bare electrode (black line). The mean value (n = 3) with the corresponding standard deviation was reported for each measurement. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)