GenScript GST tag ELISA Detection Kit is designed to quantitate glutathione-S-transferase (GST) or GST-fusion protein in samples such as cell lysate using a proprietary sandwich ELISA procedure in just 60 minutes. It utilizes two clones of GST monoclonal antibodies that bind to different epitopes of the GST tag protein at the same time. The GST monoclonal antibody, pre-coated on the plate, is used to capture GST tagged protein and the biotin conjugated GST monoclonal antibody (Biotin-GST Mab) is added to interact with GST tagged protein bound on the plate. Streptavidin-HRP is added to interact with Biotin-GST Mab and the final step involves the addition of TMB Substrate that will react with HRP to give product with an absorbance at 450 nm. The quantity of GST tagged protein in sample is determined by comparisons with the absorbance of that of a known GST tagged protein standard curve.