The TGS COVID-19 IgG test is a chemiluminescent two-step sandwich capture immunoassay (CLIA), for use on IDS-iSYS Multi-Discipline Automated System, for QUANTITATIVE determination of specific IgG class antibodies directed against the SARS-CoV-2 Spike and Nucleocapsid antigens in samples of human serum or plasma (K3-EDTA, sodium citrate, sodium heparin). The assay with excellent sensitivity and specificity is used as a diagnostic aid when assessing the immunity status of patients related to COVID-19 and is suitable for use with human serum or plasma.