Description
Principle of the Assay: The principle of the double antibody sandwich ELISA is represented in Figure 1. In this assay the Lipocalin-2/NGAL present in samples reacts with the anti-Lipocalin-2/NGAL antibodies which have been adsorbed to the surface of polystyrene microtitre wells. After the removal of unbound proteins by washing, anti-Lipocalin-2/NGAL antibodies conjugated with horseradish peroxidase (HRP), are added. These enzyme-labeled antibodies form complexes with the previously bound Lipocalin-2/NGAL. Following another washing step, the enzyme bound to the immunosorbent is assayed by the addition of a chromogenic substrate, 3,3',5,5'-tetramethylbenzidine (TMB). The quantity of bound enzyme varies directly with the concentration of Lipocalin-2/NGAL in the sample tested; thus, the absorbance, at 450 nm, is a measure of the concentration of Lipocalin-2/NGAL in the test sample. The quantity of Lipocalin-2/NGAL in the test sample can be interpolated from the standard curve constructed from the standards, and corrected for sample dilution