Highly sensitive ELISA assays require minimal non-specific interactions. Non-specific binding results in elevated background levels and a decrease in signal-to-noise ratios. Blocking reagents act to minimize non-specific interactions of secondary reactants with each other and with the primary solid phase binding sites. Supplier offers several options for antibody diluents in multiple buffer configurations that effectively block non-specific interactions and minimize background. Multiple formulations offer greater flexibility in experimental design.