Practical Protein Chemistry - A. Darbre 1989

Analytical Methods
Determination of Protein Bound to a Solid Support
Determination of the Nature of the Resin Substituent by Staining

1 ml of a saturated sodium borate solution is added to agarose or polyacrylamide (0.2–0.5 ml) swollen in Water. 3 drops of a 3% (w/v) aqueous solution of 2,4,6-trinitrobenzenesulfonic acid are added, and the mixture is left for 2 h at room Temperature to complete the reaction. Unsubstituted polymers and resins containing carboxyl and bromoacetyl groups yield a yellow coloration; derivatives containing primary aliphatic amines yield orange, aromatic amines yield red-orange, and hydrazides yield dark red.



Last update: 06/08/2026

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