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P8412

Sigma-Aldrich

o-Phenylenediamine dihydrochloride

chromogenic, tablet

Synonym(s):

1,2-Phenylenediamine tablet, OPD, OPD Tablet

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About This Item

Linear Formula:
C6H4(NH2)2·2HCl
CAS Number:
Molecular Weight:
181.06
Beilstein:
3912045
MDL number:
UNSPSC Code:
12352204
PubChem Substance ID:
NACRES:
NA.83

product name

o-Phenylenediamine dihydrochloride, tablet, 30 mg substrate per tablet

Quality Level

form

tablet

mp

258 °C (dec.) (lit.)

solubility

water: 1 tablet/10 mL, clear, colorless

storage temp.

2-8°C

SMILES string

Cl[H].Cl[H].Nc1ccccc1N

InChI

1S/C6H8N2.2ClH/c7-5-3-1-2-4-6(5)8;;/h1-4H,7-8H2;2*1H

InChI key

RIIWUGSYXOBDMC-UHFFFAOYSA-N

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General description

o-Phenylenediamine dihydrochloride is a binucleophile and its condensation with α,β-unsaturated carbonyl compounds and aldehydes yields benzimidazoles.
o-Phenylenediamine dihydrochloride (OPD) is a chromogenic substrate that can be used in enzyme-linked immunosorbent assay (ELISA) procedures as it utilizes horseradish peroxidase conjugates. The substrate produces a soluble end product that is orange-brown and can be read spectrophotometrically at 450 nm. The OPD reaction may be stopped with 3N HCl or 3M H2SO4 and read at 492 nm.

Application

o-Phenylenediamine dihydrochloride has been used as a substrate for horse radish peroxidase in detecting:
  • human immunoglobulin
  • CTLA4Ig in serum samples
  • albumin in culture medium

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.

Signal Word

Warning

Hazard Classifications

Acute Tox. 4 Inhalation - Acute Tox. 4 Oral - Aquatic Acute 1 - Aquatic Chronic 1 - Carc. 2 - Eye Irrit. 2 - Muta. 2 - Skin Sens. 1

Storage Class Code

11 - Combustible Solids

WGK

WGK 1


Certificates of Analysis (COA)

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Acetic acid-promoted condensation of o-phenylenediamine with aldehydes into 2-aryl-1-(arylmethyl)-1H-benzimidazoles under microwave irradiation
Azarifar D, et al.
J. Serb. Chem. Soc., 75(9), 1181-1189 (2010)
The reaction of o-phenylenediamine with alpha, beta-unsaturated carbonyl compounds
Claramunt RM, et al.
ARKIVOC (Gainesville, FL, United States), 14, 35-45 (2006)
Long-term graft acceptance in rat heart transplantation by CTLA4Ig gene transfection combined with FTY720 treatment
Ohba M, et al.
World Journal of Surgery, 25(4), 391-398 (2001)
In vitro and in vivo properties differ among liquid intravenous immunoglobulin preparations
Dhainaut F, et al.
Vox Sanguinis, 104(2), 115-126 (2013)
Human amniotic epithelial cells are promising transgene carriers for allogeneic cell transplantation into liver
Sakuragawa N, et al.
Journal of Human Genetics, 45(3), 171-171 (2000)

Articles

Nitroblue Tetrazolium (NBT) is used with the alkaline phosphatase substrate 5-Bromo- 4-Chloro-3-Indolyl Phosphate (BCIP) in western blotting and immunohistological staining procedures. These substrate systems produce an insoluble NBT diformazan end product that is blue to purple in color and can be observed visually.

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