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P3804

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:
615-28-1
Molecular Weight:
181.06
Beilstein:
3912045
EC Number:
210-418-7
MDL number:
MFCD00012966
UNSPSC Code:
12352204
PubChem Substance ID:
24898457
NACRES:
NA.83

product name

o-Phenylenediamine dihydrochloride, tablet, 5 mg substrate per tablet

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 (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 chromogenic substrate in indirect enzyme-linked immunosorbent assay (ELISA) to detect immunoglobin G (IgG) antibodies against certain recombinant antigens/proteins
  • as a streptavidin-horseradish peroxidase (HRP) substrate sandwich ELISA to analyze human interleukin (IL)-17A, IL-23, and IP-10
  • as a substrate in ELISA for determination of IgG-class antibodies to Mycobacterium bovis in serum

Packaging

16 mg total tablet weight

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 3

Certificates of Analysis (COA)

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