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P7288

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:
24898837
NACRES:
NA.83

product name

o-Phenylenediamine dihydrochloride, tablet, 20 mg substrate per tablet

form

tablet

mp

258 °C (dec.) (lit.)

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 for the eosinophil peroxidase (EPO) assay in bronchoalveolar lavage fluid (BALF)
  • in cell adhesion molecule-enzyme immunoassay (CAM-EIA) to analyze the amounts of E-selectin induced by test compounds (LPS or solutions and materials) on endothelial cells
  • in ultra-sensitive enzyme-linked immunosorbent assay (ELISA) to measure prolactin and luteinizing hormone (LH)

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

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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D Sano et al.
Journal of applied microbiology, 109(6), 1923-1928 (2010-08-26)
Transmission routes of noroviruses, leading aetiological agents of acute gastroenteritis, are rarely verified when outbreaks occur. Because the destination of norovirus particles being firmly captured by micro-organisms could be totally different from that of those particles moving freely, micro-organisms with
Ronald E Unger et al.
Biomaterials, 35(10), 3180-3187 (2014-01-25)
Endotoxin, also known as lipopolysaccharide (LPS) produced by bacteria can be present in any liquid or on any biomaterial even if the material is sterile. Endotoxin in mammals can cause fever, inflammation, cell and tissue damage and irreversible septic shock
Hollian R Phillipps et al.
Journal of neuroendocrinology, 34(6), e13129-e13129 (2022-05-02)
Throughout the reproductive cycle in rodents, prolactin levels are generally low. In some species, including rats, a prolactin surge occurs on proestrus with peak concentrations coinciding with the preovulatory luteinizing hormone (LH) surge. In mice, however, there are conflicting reports
C A Ison
Methods in molecular medicine, 66, 317-329 (2001-01-01)
Neisseria meningitidis is an obligate human pathogen. When it interacts with the host, it can establish a commensal relationship or can, on a minority of occasions, invade and cause systemic disease. Protection against systemic disease, particularly for serogroup A and
R W Pero et al.
Molecular and cellular biochemistry, 193(1-2), 119-125 (1999-05-20)
Our laboratory has concentrated on the possible regulation the benzamides and nicotinamides may have on the processes of DNA repair and apoptosis. Recent reports have suggested that both apoptosis and inflammation are regulated by the transcription factor NF-kappaB. We have
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