Principle of Assay
Rat Carbonic Anhydrase 4/CA4 ELISA Kit (A303766) is a 4 hour sandwich Enzyme-Linked Immunosorbent Assay (sELISA) designed for the in vitro quantitative determination of rat Carbonic Anhydrase 4/CA4 in serum, plasma, tissue homogenates, and other biological fluids. A 96-well microtiter plate has been pre-coated with an antibody specific for Carbonic Anhydrase 4/CA4. Standards and samples are added to the wells, where Carbonic Anhydrase 4/CA4 binds to the immobilized capture antibody. Following incubation, unbound components are removed by washing and a biotinylated detection antibody specific for Carbonic Anhydrase 4/CA4 is added to the wells. The detection antibody binds the captured Carbonic Anhydrase 4/CA4 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 Carbonic Anhydrase 4/CA4 captured in each well. The concentration of Carbonic Anhydrase 4/CA4 is calculated by reading the absorbance at 450 nm and comparing the values with the standard curve.