Indication of the coronavirus model particles using a nanowire biosensor

In early 2020, the world health organization (WHO) announced the coronavirus pandemic COVID-19.
According to the WHO, one of the most important factors in containing infection is the use of laboratory diagnostics. Thus, the development of new more sensitive and rapid methods of coronavirus indication and the study of its properties is an actual problem.
The goal of the research: - to study the method of indication of virus-like coronavirus particles (CVP) using a nanowire biosensor.
We used biosensors – n-channel silicon nanowire field-effect transistors (Si-NW FET) and non-pathogenic CVP based on vesicular stomatitis virus. In experiments, the concentration of CVP was changed in the range from 10-18 to 10-13 M. The CVP contained the surface protein S of the SARS-CoV-2 coronavirus on their surface. Specific antibodies to CVP were obtained based on the m396 antibody interacting with SARS.
In the process of biosensor preparation, the surface of its nanowire in the first version was modified with antibodies and APTES chemical reagent, in the second version-only with antibodies.
Directly in the process of indication, 1 ml of CVP suspension was applied to the surface of the nanowire with a pipette and the current in the source-drain circuit of the transistor was registered.

Results:
- antibody + CVP complexes at the interface with the surface of the nanowire modulate the current of the field-effect transistor;
- CVP have a positive electric charge at the interface " nanowire surface - viral suspension»;
- antibody + CVP complexes have a negative electric charge at the interface section " nanowire surface -- viral suspension»;
- the sensitivity of the biosensor is about 10-18 M;
- the display time was 200-300 seconds.