Principle of Assay
Ractopamine ELISA Test Kit (A327241) employs the competitive enzyme immunoassay technique for the quantitative measurement of Ractopamine in feed, tissue, milk, milk powder and egg. The 96-well microtiter plate has been pre-coated with Ractopamine. During the incubation, Ractopamine present in the samples or standards competes with the fixed amount of immobilized Ractopamine for binding sites of the Anti-Ractopamine Antibody, a HRP-Conjugated Secondary Antibody is added to the wells at the same time. The more Ractopamine present in a sample or standard, the less Anti-Ractopamine Antibody that binds to the plate. Following incubation, unbound HRP-Conjugated Secondary Antibody is removed by washing. Following incubation and washing, TMB substrate solution is then used to visualize the HRP enzymatic reaction by catalysis to produce a blue-coloured product that changes to yellow after addition of acidic stop solution. The density of yellow is inversely proportional to the amount of Ractopamine present in each sample or standard. The concentration of Ractopamine can then be calculated by reading the O.D. absorbance at 450nm in a microplate reader and referring to the standard curve.
