Description
Principle of the Assay: Apl/APA ELISA kit applies the competitive enzyme immunoassay technique utilizing phospholipid antigen and an Apl/APA -HRP conjugate. The assay sample and buffer are incubated together with Apl/APA -HRP conjugate in pre-coated plate for one hour. After the incubation period, the wells are decanted and washed five times. The wells are then incubated with a substrate for HRP enzyme. The product of the enzyme-substrate reaction forms a blue colored complex. Finally, a stop solution is added to stop the reaction, which will then turn the solution yellow. The intensity of color is measured spectrophotometrically at 450nm in a microplate reader. The intensity of the color is inversely proportional to the Apl/APA concentration since Apl/APA from samples and Apl/APA HRP conjugate compete for the phospholipid antigen binding site. Since the number of sites is limited, as more sites are occupied by Apl/APA from the sample, fewer sites are left to bind Apl/APA HRP conjugate. A standard curve is plotted relating the intensity of the color (O.D.) to the concentration of standards. The Apl/APA concentration in each sample is interpolated from this standard curve