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Thermo Scientific™ TNBSA Solution (2,4,6-trinitrobenzene sulfonic acid) (5% w/v)

Label primary amines (peptides or amino acids) for colorimetric detection (Amax 335nm) using this 5% solution of trinitrobenzene sulfonic acid in methanol.

Supplier:  Thermo Scientific™ 28997

Catalog No. PI28997

Item Discontinued This item has been discontinued by the supplier. Please to view product availability in your area.



Thermo Scientific™ Pierce TNBSA is a 5% solution of trinitrobenzene sulfonic acid in methanol that reacts with primary amines (peptides or amino acids) to yield a soluble colored product, a property useful for various assay methods.


  • Couples with primary amines, sulfhydryls and hydrazides in aqueous solution at pH 8, without undesirable side reactions
  • Excellent for solution or solid phase analysis
  • Suitable for qualitative and quantitative estimation of biomolecules
  • λmax = 335nm
  • Reacts readily with primary amino groups of amino acids in aqueous format at pH 8 to form yellow adducts
  • No colored derivatives are formed with secondary amino acids proline and hydroxyproline
  • Colored derivatives are monitored at 345nm and have extinction coefficients in range of 1-1.5 x 104


TNBSA Solution
Storage: Upon receipt store at -20°C. Product is shipped at ambient temperature.
Other Label or Dye
100 mL
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