Fig. 4.

The performance of the Bi-ECDAQ sensing platform (combined immuno-biosensor and the potentiostat readout) for electrochemical detection of SARS-CoV-2 Alpha variant real-time polymerase chain reaction (RT-PCR) positive and negative nasopharyngeal (NP) swab samples. A) Charge transfer resistance signals measured for each of WEs for each sample and control groups and their comparison with the corresponding cycle threshold (Ct) values of RT-PCR. B) The paired WEs generated by the Bi-ECDAQ reader, resulting in the self-validation of COVID-19 detection performed by the Bi-ECDAQ.