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Protein A Sandwich ELISA - Protein A orients Capture Ab-Antigen-primary Ab-detector Ab (Aug/03/2010 )

Im trying to use a Protein A Coated ELISA plate for a sandwich ELISA. After I coat my rabbit capture antibody can I block the remaining Protein A sites with FBS?


I saw no one was jumping in to respond. I would block the unreacted sites with a known mass/concentration of non-specific IgG. This would be necessary if the protein A reacts with conjugate or secondary ab or label.

If you use serum you do not know exactly the mass of non-specific IgG you are adding. This may not be a problem...but if you have access to some bulk IgG I would use that.