Xanthoproteic test: Principle, Reaction | 合法醫療器材資訊網

2020年4月5日—Yellowishsubstanceproducedbyheatingproteinwithnitricacidisxanthoprotein​,hencethenamexanthoproteicforthetest.Thistestis ...

Xanthoproteic test

Detection of aromatic amino acids

Yellowish substance produced by heating protein with nitric acid is xanthoprotein, hence the name xanthoproteic for the test. This test is performed to identify the amino acid having benzene ring in them like tyrosine, tryptophan, and phenylalanine.

Principle:

Treating aromatic amino acids with the concentrated nitric acid leads to the nitration of the aromatic ring and formation of yellow nitro-products (nitro derivatives). When the strong basic solution is added the colour of obtained products turns darker (from yellow to orange). The positive result of xanthoproteic reaction gives: tyrosine, tryptophan and phenylalanine...