Description

• Application: o-Phenylenediamine Free Base is a peroxidase substrate suitable for use in ELISA procedures. The substrate produces a soluble end product that is orange-brown in color and can be read spectrophotometrically at 450 nm. The OPD reaction may be stopped with 3 N HCl or 3 M H2SO4 and read at 492 nm.
• Biochem/physiol Actions: o-Phenylenediamine (o-PD) is a potent substrate for spectrophotometric horseradish peroxidase (HRP)-mediated enzyme-linked immunosorbent assay (ELISA), which gives 2,3-diaminophenazine (DAP) as a product of o-PD oxidation.[3]
• Reconstitution: Dissolve one tablet in 0.05 M phosphate-citrate buffer, pH 5.0, to the desired concentration (typically an OPD concentration of 0.4 mg/ml is used). Add 40 μl of fresh 30% hydrogen peroxide per 100 ml of substrate buffer solution, immediately prior to use. Tablets are individually packaged in foil packets.