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P4664

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, 15 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 (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 in conventional capture enzyme-linked immunosorbent assay (ELISA) for recombinant hemagglutinin (rHA) protein detection
  • as a substrate for the determination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) antibodies by ELISA
  • as a colorimetric reagent specific for horseradish peroxidase (HRP) activity assessment in an ELISA protocol using SARS-CoV-2 antigens for S protein

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

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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