Principle of Assay
Human Complement Factor I ELISA Kit (A79200) is a 4 hour sandwich Enzyme-Linked Immunosorbent Assay (sELISA) designed for the in vitro quantitative determination of human Complement Factor I in serum, plasma, tissue homogenates, and other biological fluids. A 96-well microtiter plate has been pre-coated with an antibody specific for Complement Factor I. Standards and samples are added to the wells, where Complement Factor I binds to the immobilized capture antibody. Following incubation, unbound components are removed by washing and a biotinylated detection antibody specific for Complement Factor I is added to the wells. The detection antibody binds the captured Complement Factor I 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 Complement Factor I captured in each well. The concentration of Complement Factor I is calculated by reading the absorbance at 450 nm and comparing the values with the standard curve.