2,4,6-Trinitrobenzenesulfonic acid - 5% Aqueous solution

2,4,6-Trinitrobenzenesulfonic acid (also known as TNBS, TNSBA or picrylsulfonic acid) is a strongly oxidising organic acid that has long been used as a reagent to determine the presence of free primary amine groups. TNBS reacts rapidly with primary amines to form highly coloured N-trinitrophenyl acid products which can then be analysed by colorimetry. The amine can be regenerated by treatment with hydrazine. This analytical technique can also be applied to thiols and hydrazides. As is common with nitrated aromatic compounds, there is a risk of explosion and TNBS is typically commercially available as a solution. We also supply the 1% solution in DMF.