The 3M Coconut Protein ELISA Kit utilizes a sandwich ELISA. The coconut proteins present in the sample react with the anti-coconut antibody, which have been adsorbed to the surface of polystyrene microtiter wells. After the removal of unbound proteins by washing, anti-coconut antibodies conjugated with horseradish peroxidase (HRP) are added. These enzyme-labeled antibodies form complexes with the previously bound coconut protein. Following a second washing step, the enzyme bound to the immunosorbent is detected by the addition of a chromogenic substrate, 3,3’,5,5’-tetramethylbenzidine (TMB). The color development from this enzymatic reaction varies directly with the concentration of coconut protein in the sample tested; thus, the absorbance, at 450 nm, is a measure of the concentration of coconut protein in the test sample. The quantity of coconut protein in the test sample can be extrapolated from the standard curve, constructed from standards of known concentration, and adjusted to consider the sample dilution.