PRINCIPLE OF THE TESTThe COVID-19 Antigen Rapid Test Cassette is an immunochromatographic membraneassay that uses highly sensitive monoclonal antibodies to detect nucleocapsid proteinfrom SARS-CoV-2 in nasopharyngeal (NP) swab. The test strip is composed of thefollowing parts: namely sample pad, reagent pad, reaction membrane, and absorbingpad. The reagent pad contains the colloidal-gold conjugated with the monoclonalantibodies against the nucleocapsid protein of SARS-CoV-2; the reaction membranecontains the secondary antibodies for nucleocapsid protein of SARS-CoV-2. The wholestrip is fixed inside a plastic device. When the sample is added into the sample well,conjugates dried in the reagent pad are dissolved and migrate along withthe sample.If SARS-CoV-2 antigen presents in the sample, a complex formed between theanti-SARS-2 conjugate and the virus will be captured by the specific anti-SARS-2monocional antibodies coated on the test line region (T). Absence of the T linesuggests a negative result. To serve as a procedural control, a red line will alwaysappear in the control line region (C) indicating that proper volume of sample has beenadded and membrane wicking has occurred.