Recombinant Glutathione S Transferase Pi (GSTp) is a key enzyme in the body. It conjugates glutathione with electrophilic substances, playing a vital role in detoxification and antioxidant defense. GSTp is involved in protecting cells from harmful substances and oxidative stress by binding with PRDX6 .Thus a functional ELISA assay was conducted to detect the interaction of recombinant rat GSTp and recombinant rat PRDX6. Briefly, GSTp was diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to PRDX6-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-GSTp pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody for 1h at 37℃, wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50 µL stop solution to the wells and read at 450/630nm immediately. The binding activity of recombinant rat GSTp and recombinant rat PRDX6 was shown in Figure 1, the EC50 for this effect is 0.008ug/mL.