Rapid SARS-CoV-2 S-protein Detection using Nanostructured Electrochemical Biosensor

We have developed a new type of testing strategy based on the electrochemical biosensing aspect for rapid and portable detection of SARS-CoV-2. The detection platform is based on a highly conductive matrix (fabricated polystyrene/polyaniline-Au nanocomposite) enabling immobilization of representative receptor elements (antibodies) that are specific to the target, i.e., SARS-CoV-2 spike (S)-protein. The concept of a detection system is to translate specific covalent interaction between antibodies and its corresponding binding viral S-protein, into a measurable, concentration-dependent electrochemical signal. The biosensor is able to monitor the electrochemical response in PBS, without using hazardous [Fe(CN)]63-/4- redox couple. By creating an electrochemical readout (CV, EIS, and DPV), data enables qualitative and quantitative analysis. Additionally, it exploits outstanding conductivity and biocompatibility, thus resulting in high analytical sensitivity and a low detection limit of
$15.6\ \mu g/mL$
, which is within the physiologically relevant concentration range. Thus, the proposed feasible design of the biosensor platform represents an excellent starting point for practical and low-cost testing of asymptomatic patients or people before symptom onset.