This PBS based antibody diluent can be used to dilute both primary and secondary antibodies for IHC, ICC, IF and whole mount staining. Serum blocking step can be omitted when using this product and it is particularly useful for enhancing staining intensity and reducing background staining without diminish specific immunoreactivity. There is no preservative added so it can be used to dilute HRP conjugated antibodies. Due to inhibition effect of phosphate on alkaline phosphatase, this diluent should NOT be used for diluting Alkaline Phosphatase labeled antibodies.