Fig. 3.
Analytical performance of the Bi-ECDAQ potentiostat reader for measuring spiked concentrations of SARS-CoV-2 N-protein in PBS using the N-protein immuno-biosensor. A) Electrochemical characterization (in terms of Rct response) of the stepwise surface modification of the immuno-biosensors on both WEs measured by Bi-ECDAD and APG. B) Nyquist plot representation and calibration curves of the EIS measurements performed by Bi-ECDAQ for various concentrations of N-protein analyte. C) Nyquist plot representation and calibration curves of EIS response measured by Autolab potentiostat for various concentrations of N-protein spiked in PBS. D) Rct values representing the independent response of WE1 from WE2, when only WE1 is modified with antibody and BSA while WE2 remained bare. The measurements were performed using both Bi-ECDAC and APG readers.