Rapid, cheap and accurate tests continue to be essential for epidemiological surveillance and for health services to monitor and contain the spread of SARS-CoV-2. Brazilian scientists have contributed to endeavors in this field by developing an electrochemical immunosensor that detects antibodies against the virus.
The innovation is described in an article published recently in the journal ACS Biomaterials Science and Engineering.
In search of a novel diagnostic method, the group opted for a material frequently used in metallurgy – zinc oxide – and combined it for the first time with fluorine-doped tin oxide (FTO) glass, a conductive material used in electrodes for photovoltaics and other advanced applications.
"With this unusual combination and the addition of a biomolecule, the viral spike protein, we developed a surface capable of detecting antibodies against SARS-CoV-2. The result is displayed as an electrochemical signal captured by this surface," said chemist Wendel Alves, lead author of the article. Alves is a professor at the Center for Natural and Human Sciences, Federal University of the ABC (UFABC), São Paulo state.
The electrode fabricated by the researchers detected COVID-19 antibodies in serum in about five minutes with 88.7% sensitivity and 100% specificity, outperforming even the enzyme-linked immunosorbent assay (ELISA) test, the current gold-standard clinical diagnostic tool.
The research was supported by FAPESP via the National Science and Technology Institute for Bioanalysis and a Thematic Project.
According to Alves, who heads UFABC's Electrochemistry and Nanostructured Materials Laboratory, prior knowledge…