Principle of Assay
Human Thymidine Phosphorylase ELISA Kit (A79763) is a 4 hour sandwich Enzyme-Linked Immunosorbent Assay (sELISA) designed for the in vitro quantitative determination of human Thymidine Phosphorylase in serum, plasma, tissue homogenates, and other biological fluids. A 96-well microtiter plate has been pre-coated with an antibody specific for Thymidine Phosphorylase. Standards and samples are added to the wells, where Thymidine Phosphorylase binds to the immobilized capture antibody. Following incubation, unbound components are removed by washing and a biotinylated detection antibody specific for Thymidine Phosphorylase is added to the wells. The detection antibody binds the captured Thymidine Phosphorylase to form an antibody-antigen-antibody sandwich complex. After further incubation and washing, HRP-Streptavidin conjugate is added to the wells. TMB substrate solution is then added to visualize the HRP enzymatic reaction. This produces a blue-coloured product that changes to yellow following addition of acidic stop solution. The intensity of the yellow colour is directly proportional to the amount of Thymidine Phosphorylase captured in each well. The concentration of Thymidine Phosphorylase is calculated by reading the absorbance at 450 nm and comparing the values with the standard curve.