Discrimination of the H1N1 and H5N2 Variants of Influenza A Virus Using an Isomeric Sialic Acid-Conjugated Graphene Field-Effect Transistor

There has been a continuous effort to fabricate a fast, sensitive, and inexpensive system for influenza virus detection to meet the demand for effective screening in point-of-care testing. Herein, we report a sialic acid (SA)-conjugated graphene field-effect transistor (SA-GFET) sensor designed using alpha 2,3-linked sialic acid (3 '-SA) and alpha 2,6-linked sialic acid (6 '-SA) for the detection and discrimination of the hemagglutinin (HA) protein of the H5N2 and H1N1 viruses. 3 '-SA and 6 '- SA specific for H5 and H1 influenza were used in the SA-GFET to capture the HA protein of the influenza virus. The net charge of the captured viral sample led to a change in the electrical current of the SA-GFET platform, which could be correlated to the concentration of the viral sample. This SA-GFET platform exhibited a highly sensitive response in the range of 101-106 pfu mL-1, with a limit of detection (LOD) of 101 pfu mL-1 in buffer solution and a response time of approximately 10 s. The selectivity of the SA-GFET platform for the H1N1 and H5N2 influenza viruses was verified by testing analogous respiratory viruses, i.e., influenza B and the spike protein of SARS-CoV-2 and MERS-CoV, on the SA-GFET. Overall, the results demonstrate that the developed dual-channel SA-GFET platform can potentially serve as a highly efficient and sensitive sensing platform for the rapid detection of infectious diseases.

Automated summary

A novel sialic acid-conjugated graphene field-effect transistor (SA-GFET) sensor has been developed for fast, sensitive, and inexpensive detection of influenza viruses, with the ability to distinguish different strains. The sensor captures the hemagglutinin (HA) protein of the viruses and detects their concentration by measuring the change in electrical current. The SA-GFET platform demonstrates high sensitivity, selectivity, and potential for rapid detection of infectious diseases.