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D8130

Sigma-Aldrich

5,5′-Dithiobis(2-nitrobenzoic acid)

≥98%, BioReagent, suitable for determination of sulfhydryl groups

Synonym(s):
3-Carboxy-4-nitrophenyl disulfide, 6,6′-Dinitro-3,3′-dithiodibenzoic acid, Bis(3-carboxy-4-nitrophenyl) disulfide, DTNB, Ellman’s Reagent
Linear Formula:
[-SC6H3(NO2)CO2H]2
CAS Number:
Molecular Weight:
396.35
Beilstein:
1896821
EC Number:
MDL number:
PubChem Substance ID:
NACRES:
NA.26

product line

BioReagent

Quality Level

Assay

≥98%

form

powder

mp

240-245 °C (dec.) (lit.)

suitability

suitable for determination of sulfhydryl groups

SMILES string

OC(=O)c1cc(SSc2ccc(c(c2)C(O)=O)[N+]([O-])=O)ccc1[N+]([O-])=O

InChI

1S/C14H8N2O8S2/c17-13(18)9-5-7(1-3-11(9)15(21)22)25-26-8-2-4-12(16(23)24)10(6-8)14(19)20/h1-6H,(H,17,18)(H,19,20)

InChI key

KIUMMUBSPKGMOY-UHFFFAOYSA-N

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General description

5,5′-Dithiobis(2-nitrobenzoic acid) is also called DTNB or Ellman′s reagent. It is a water soluble reagent, which interacts with thiol groups, and can be used conveniently at neutral pH. Thiolate anion (RS-) reacts with Ellman′s reagent (DTNB2-), to produce 2-nitro-5-thiobenzoate anion (TNB2-) and one mixed disulfide (R-S-TNB-). TNB2- has a high molar absorption coefficient, and absorbs at 412nm. This absorption is independent of pH, at pH> 7.3.

Application

Ellman′s reagent maybe used for acetylcholinesterase assay, and to specifically label cysteine residues. It is a sensitive reagent for measuring the free sulfhydryl content in proteins, peptides, and tissues.

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

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