DTNB

DTNB or 5,5'-Dithiobis(2-nitrobenzoic acid) is a chemical reagent often used in scientific research. It is also known by the name Ellman's reagent. DTNB is a compound that measures the concentration of thiol groups in a solution.

Chemical Properties

DTNB is a yellow crystalline powder that is soluble in water and alcohol. It has a molecular weight of 396.35 g/mol and a melting point of 198-200°C. The chemical formula for DTNB is C14H8N2O8S2.

Uses

DTNB is primarily used in biochemistry for the quantification of protein thiols. It reacts with thiols to form a mixed disulfide and 2-nitro-5-thiobenzoate (TNB), which is a yellow compound that can be detected spectrophotometrically at 412 nm. This reaction is the basis for the Ellman's test, a common method for quantifying free thiols in solution.

Safety

DTNB is considered a low hazard compound. However, it can cause skin and eye irritation, and should be handled with care. It should be stored in a cool, dry place, away from light.

See Also

• Ellman's test
• Thiol
• Protein