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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

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500 MG
€30.80
1 G
€54.70
5 G
€140.00
10 G
€249.00
25 G
€502.00
100 G
€2,020.00

€30.80

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500 MG
€30.80
1 G
€54.70
5 G
€140.00
10 G
€249.00
25 G
€502.00
100 G
€2,020.00

About This Item

Linear Formula:
[-SC6H3(NO2)CO2H]2
CAS Number:
69-78-3
Molecular Weight:
396.35
Beilstein:
1896821
EC Number:
200-714-4
MDL number:
MFCD00007140
UNSPSC Code:
12352106
PubChem Substance ID:
24894189
NACRES:
NA.26

€30.80

In StockDetails

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product line

BioReagent

Quality Level

200

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.[1] It is a water soluble reagent, which interacts with thiol groups, and can be used conveniently at neutral pH.[2] 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.[3]

Application

Ellman′s reagent maybe used for acetylcholinesterase assay, and to specifically label cysteine residues.[2] 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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Certificates of Analysis (COA)

Lot/Batch Number
0000340525
0000340535
WXBF2505V
WXBF3196V
WXBF3940V

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Ellman's reagent: 5,5'-dithiobis(2-nitrobenzoic acid)--a reexamination.
P W Riddles et al.
Analytical biochemistry, 94(1), 75-81 (1979-04-01)
Christian K Riener et al.
Analytical and bioanalytical chemistry, 373(4-5), 266-276 (2002-07-12)
Since its introduction in 1959, Ellman's reagent (5,5'-dithio-bis(2-nitrobenzoic acid)) has been the favorite reagent for spectrophotometric measurement of protein sulfhydryls. Meanwhile however, evidence has accumulated that many protein sulfhydryls give an incomplete reaction with Ellman's reagent, even during prolonged assay
Reassessment of Ellman's reagent.
P W Riddles et al.
Methods in enzymology, 91, 49-60 (1983-01-01)
Venkaiah Betapudi et al.
Science translational medicine, 12(527) (2020-01-24)
Chemical warfare nerve agents are organophosphorus chemical compounds that induce cholinergic crisis, leaving little or no time for medical intervention to prevent death. The current chemical treatment regimen may prevent death but does not prevent postexposure complications such as brain
Anne Bertling et al.
Arteriosclerosis, thrombosis, and vascular biology, 32(8), 1979-1990 (2012-04-28)
Staphylococcus aureus can induce platelet aggregation. The rapidity and degree of this correlates with the severity of disseminated intravascular coagulation, and depends on platelet peptidoglycans. Surface-located thiol isomerases play an important role in platelet activation. The staphylococcal extracellular adherence protein
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Protocols

Enzymatic Assay of Chloramphenicol Acetyltransferase

To measure chloramphenicol acetyltransferase activity, this procedure uses DTNB and coenzyme A. The reaction of DTNB with the –SH group on CoA results in a colorimetric increase at 412 nm.

Questions

1–4 of 4 Questions  

  1. How is shipping temperature determined? And how is it related to the product storage temperature?

    1 answer

    1. Products may be shipped at a different temperature than the recommended long-term storage temperature. If the product quality is sensitive to short-term exposure to conditions other than the recommended long-term storage, it will be shipped on wet or dry-ice. If the product quality is NOT affected by short-term exposure to conditions other than the recommended long-term storage, it will be shipped at ambient temperature. As shipping routes are configured for minimum transit times, shipping at ambient temperature helps control shipping costs for our customers. For more information, please refer to the Storage and Transport Conditions document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/316/622/storage-transport-conditions-mk.pdf

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  2. How can I determine the shelf life / expiration / retest date of this product?

    1 answer

    1. If this product has an expiration or retest date, it will be shown on the Certificate of Analysis (COA, CofA). If there is no retest or expiration date listed on the product's COA, we do not have suitable stability data to determine a shelf life. For these products, the only date on the COA will be the release date; a retest, expiration, or use-by-date will not be displayed.
      For all products, we recommend handling per defined conditions as printed in our product literature and website product descriptions. We recommend that products should be routinely inspected by customers to ensure they perform as expected.
      For products without retest or expiration dates, our standard warranty of 1 year from the date of shipment is applicable.
      For more information, please refer to the Product Dating Information document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/449/386/product-dating-information-mk.pdf

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  3. To dissolve DTNB which alcohol should use?

    1 answer

    1. This product is tested for solubility in Ethanol at 10 mg/mL. Solutions may also be prepared at 5mM in 100 mM sodium or potassium phosphate buffer, pH 7.2, containing 0.1 mM EDTA. Please see the link below to review the entire product datasheet for additional information:
      https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/product/documents/414/707/d8130pis.pdf

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  4. what is the storage temperature for this chemical

    1 answer

    1. This product can be stored at room temperature.

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