Protein A ELISA KIT

Protein A ELISA kit applies the quantitative sandwich enzyme immunoassay technique. The microtiter plate has been pre-coated with a monoclonal antibody specific for Protein A. Samples containing Protein A are first diluted in the Sample Diluent provided with the kits. The Denaturing Buffer is then added and mixed to dissociate the Protein A from the product antibody. The samples are then reacted in microtiter strips coated with a monoclonal anti-Protein A capture antibody. A second anti-Protein A biotinylated monoclonal antibody is simultaneously reacted forming a sandwich complex of solid phase antibody-Protein A: biotin labeled antibody. After a wash step to remove any unbound reactants, Streptavidin labeled HRP is added to each well. After a short incubation period, the strips are then reacted with TMB substrate. The enzyme-substrate reaction is terminated by addition of a sulphuric acid solution and the color change is measured spectrophotometrically at a wavelength of 450 nm. A standard curve is plotted relating the intensity of the color (OD) to the concentration of standards. The Protein A concentration in each sample is interpolated from this standard curve.

The stability of ELISA kit is determined by the loss rate of activity. The loss rate of this kit is less than 10% prior to the expiration date under appropriate storage condition.