The Sofia 2 SARS Antigen FIA uses immunofluorescence technology in a sandwich design to detect nucleocapsid protein from SARS-CoV-2 AND Influenza A&B. This test allows for the detection of SARS-CoV-2 AND Influenza A&B.

The patient sample is placed in the Reagent Tube, during which time the virus particles in the sample are disrupted, exposing internal viral nucleoproteins. After disruption, the sample is dispensed into the Test Cassette sample well. From the sample well, the sample migrates through a test strip containing various unique chemical environments. If SARS-CoV or SARS-CoV-2 or Influenza A&B viral antigens are present, they will be trapped in a specific location.