Principle of Assay
Rat Carboxypeptidase B/CPB ELISA Kit (A79944) is a 4 hour sandwich Enzyme-Linked Immunosorbent Assay (sELISA) designed for the in vitro quantitative determination of rat Carboxypeptidase B/CPB in serum, plasma, tissue homogenates, and other biological fluids. A 96-well microtiter plate has been pre-coated with an antibody specific for Carboxypeptidase B/CPB. Standards and samples are added to the wells, where Carboxypeptidase B/CPB binds to the immobilized capture antibody. Following incubation, unbound components are removed by washing and a biotinylated detection antibody specific for Carboxypeptidase B/CPB is added to the wells. The detection antibody binds the captured Carboxypeptidase B/CPB 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 Carboxypeptidase B/CPB captured in each well. The concentration of Carboxypeptidase B/CPB is calculated by reading the absorbance at 450 nm and comparing the values with the standard curve.