Coronavirus Label-Free Immunosensor: Preliminary Results

Real-time detection of airborne infection agents present in human breath and environmental airways, such as the human respiratory Coronavirus, is important for public health. For this, a model label-free immunosensor, based on multi-walled nanotubes (MWNT)-based screen-printed graphite electrodes (SPEs), was proposed and studied. For sensing applications, MWNTs have many advantages such as small size with larger surface area, excellent electron transfer promoting ability when used for antibody immobilization, with retention of its selectivity for potential immunosen-sors development. In order to verify the selectivity of the selected primary antibody (anti-CoV 229E antibody) and the effective immunocomplex formation (antigen-antibody interaction, an in-depth voltammetric characterization of MWNT-SPEs in-terface was carried out during the multistep fabrication of CoV immunosensor using [Fe(CN)6]3-/4- as an electroactive probe. After that, the analytical robustness of the performances of these immunosensing platforms was estimated and verified. Indeed, a nanomolar range detection limit (180 TCID50/mL)g/mL) with excellent reproduci-bility (RSD%=8%) was obtained.