Thermo Scientific™ Pierce DTNB (Ellman's Reagent) reacts with sulfhydryl groups to yield a colored product, which provides a reliable method for measure free reduced cysteines and other free sulfhydryls in solution
A solution of this compound produces a measurable yellow-colored product when it reacts with sulfhydryls
Consequently, Ellman's Reagent is very useful as a sulfhydryl assay reagent because of its specificity for –SH groups at neutral pH, high molar extinction coefficient and short reaction time
Sulfhydryl groups may be estimated in a sample by comparison to a standard curve composed of known concentrations of a sulfhydryl-containing compound such as cysteine
Alternatively, sulfhydryl groups may be quantitated by reference to the extinction coefficient of TNB
Highlights: Sulfhydryl detection – reacts quantitatively with free (reduced) sulfhydryl groups Colorimetric –yields colored product to enable spectrophotemetric measurement in tubes or microplates Proven assay method – well-characterized chemistry enables quantitation of peptide or protein sulfhydryl groups using extinction coefficient calculation or by comparison to a cysteine standard