Principle of Assay
Human Pepsinogen II ELISA Kit (A303002) is a 4 hour sandwich Enzyme-Linked Immunosorbent Assay (sELISA) designed for the in vitro quantitative determination of human Pepsinogen II in serum, plasma, tissue homogenates, and other biological fluids. A 96-well microtiter plate has been pre-coated with an antibody specific for Pepsinogen II. Standards and samples are added to the wells, where Pepsinogen II binds to the immobilized capture antibody. Following incubation, unbound components are removed by washing and a biotinylated detection antibody specific for Pepsinogen II is added to the wells. The detection antibody binds the captured Pepsinogen II 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 Pepsinogen II captured in each well. The concentration of Pepsinogen II is calculated by reading the absorbance at 450 nm and comparing the values with the standard curve.