Biomaterial Database

Spectrophotometric quantification of horseradish peroxidase with o-phenylenediamine. 2010

Sara Fornera, and Peter Walde

Department of Materials, ETH Zürich, CH-8093 Zürich, Switzerland.

The assay conditions for the spectrophotometric quantification of horseradish peroxidase (HRP) with the chromogenic substrate o-phenylenediamine (OPD) at 25°C in the presence of hydrogen peroxide (H(2)O(2)) were optimized. With [OPD](0)=3.14 mM and [H(2)O(2)](0)=80 μM at pH 7.2, the initial formation of only one of the possible reaction products and intermediates, 2,3-diaminophenazine (DAP, λ(max)=417 nm), was observed. The rate of DAP formation during the first 30 min of reaction was followed spectrophotometrically and found to linearly depend on the HRP concentration between 5 and 45 pM under the conditions used.

UI	MeSH Term	Description	Entries
D010619	Phenazines
D010655	Phenylenediamines	Aniline compounds that contain two amino groups. They are used as a precursor in the synthesis of HETEROCYCLIC COMPOUNDS and POLYMERS. p-Phenylenediamine is used in the manufacture of HAIR DYES and is an ALLERGEN.
D006735	Horseradish Peroxidase	An enzyme isolated from horseradish which is able to act as an antigen. It is frequently used as a histochemical tracer for light and electron microscopy. Its antigenicity has permitted its use as a combined antigen and marker in experimental immunology.	Alpha-Peroxidase,Ferrihorseradish Peroxidase,Horseradish Peroxidase II,Horseradish Peroxidase III,Alpha Peroxidase,II, Horseradish Peroxidase,III, Horseradish Peroxidase,Peroxidase II, Horseradish,Peroxidase III, Horseradish,Peroxidase, Ferrihorseradish,Peroxidase, Horseradish
D006861	Hydrogen Peroxide	A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.	Hydrogen Peroxide (H2O2),Hydroperoxide,Oxydol,Perhydrol,Superoxol,Peroxide, Hydrogen
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D013053	Spectrophotometry	The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.