Diagnostic Method for COVID-19 Using Sugar Chain-Immobilized Nanoparticles and Saliva Specimens.

Identification of viruses that infects animals or plants, and determination of their quantity are essential for the diagnosis of infectious disease and for the determination of a strategy in the treatment of virus-derived diseases. However, the concentration of viruses existing in a living body (in bodily fluid), food, drinking water, river water, and so on. is not high enough to be detected using conventional diagnostic methods. For example, since the concentration of influenza virus released from an infected person is less than the detection limit of conventional simple examination kits (rapid kit) or even a PCR process at the initial stage of infection, it is difficult to detect the presence of influenza virus which will lead to influenza disease. Our technology allows for safe, efficient, and selective concentration of viruses without troublesome ultracentrifugation, using sugar chain-immobilized metal nanoparticles based on the binding interaction between viruses and sugar chains. For COVID-19, we have developed and commercialized two molecular diagnosis kits: SUDx SARS-CoV-2 detection kit, and SGNP nCoV/Flu PCR detection kit, for the Japanese market in 2020.