Ferr is a universal intracellular protein that stores iron and releases it in a controlled fashion. The protein is produced by almost all living organisms, including algae, bacteria, higher plants, and animals. In humans, it acts as a buffer against iron deficiency and iron overload. Ferritin is found in most tissues as a cytosolic protein, but small amounts are secreted into the serum functioning as an iron carrier. Plasma ferritin is also an indirect marker of the total amount of iron stored in the body. Hence serum ferritin is used as a diagnostic test for iron-deficiency anemia.

The Biotime SARS-CoV-2 IgG/IgM Rapid Qualitative Test is intended to qualify the SARS-CoV-2 IgG and IgM antibody in human plasma, serum or whole blood by colloidal gold immunochromatography assay. The test can be used as an aid detection to SARS-CoV-2 infection and thus caused COVID-19 disease.