Peroxide Block: Endogenous peroxidase is most commonly encountered in red blood cells, kidney, and liver tissue. Peroxide Block should be used prior to application of primary antibody when Horseradish Peroxidase (HRP) is used as the labeling enzyme, and if it is necessary to block endogenous peroxidase activity in the tissue being stained.
Power Block™: This is a blocking reagent for reducing nonspecific background in immunoassays. A truly universal block, it is suitable for use in immunohistochemistry, immunocytochemistry, ELISA methods, and immunogold techniques. The Power Block reagent contains buffer, casein and preservative and also works well as an antibody diluent and washing medium.
Protein Block: This can be used to reduce background staining due to non-specific binding of the primary or secondary antibodies to the tissue. Protein Block should be applied immediately prior to the primary antibody.