This article was originally published here

Taranta. November 29, 2021; 239:123113. doi: 10.1016/j.talanta.2021.123113. Online before printing.

Carbon immunosensor is an ideal nano-platform for the development of rapid, accurate and ultra-specific diagnostic kits, which can detect viral infectious diseases such as COVID-19 early. However, the development of a suitable carbon immunosensor requires a step-by-step agreement to find the best operating conditions to minimize disadvantages. Here, for the first time, multi-walled carbon nanotubes (MWCNT) are performed under two different outer diameters (OD), namely 20-30 nm and 50-80 nm, through step-by-step protocol, activation, and monoclonal IgG antibody installation capabilities, and Graphene derivatives (graphene oxide (GO) and reduced graphene oxide (rGO)) were examined and compared with each other to find the main carbonaceous nanomaterials to maximize the antibody loading efficiency and the ideal detection limit (DL ) And sensitivity. Next, we carefully evaluated the effects of common amplifying agents, namely gold nanostars (Au NSs) and silver nanowires (Ag NWs) on the overall performance of the best carbonaceous structure, and studied the responsible detection mechanism in detail. Next, the developed carbon immunosensors were evaluated by voltammetry and impedance measurement, and their performance in specific detection of SARS-CoV-2 antigen through immune response was examined in detail. Research results show that, compared with other 1D/2D carbonaceous nanomaterials, rGO-based coupled immunosensors and Au NSs have excellent specificity and rapid (1 minute) detection of SARS-CoV-2 antigen in biological fluids. performance.