Chemiluminescent substrates provide a higher degree of sensitivity than other substrates to enable lower limits of detection to be achieved in ELISA & Western Blot assays. The increase in sensitivity requires more vigilance during the optimization process through the proper selection of the luminol substrate, antibody/antigen titers and blockers. Surmodics provides multiple 2-component HRP chemiluminescent substrates with various intensities to allow the assay developer to choose the appropriate substrate for the application. Benefits: 1) Picogram to femtogram levels of sensitivity 2) High signal-to-noise ratios