ARGININE TEST (Test for Guanidine Group):
Arginine test is specific for Arginine and indicates the presence of guanidine group in the arginine molecule.
- Protein solution
- 5% sodium hydroxide
- 1% alcoholic α-naphthol
- sodium hypobromite (NaOBr)
- Take 1 ml of original solution (protein solution) in a test tube.
- Add 1 ml of 5% sodium hydroxide to the test tube.
- And add 2 drops of 1% alcoholic α-naphthol.
- Mix it and add 3 drops of sodium hypobromite (NaOBr) reagent.
- Mix it thoroughly.
- A bright red colour is formed. This confirms the presence of arginine.
When bright red colour forms, it mean arginine is present in the solution.
- Wash the apparatus before and after the experiment.
- Carefully handle all the chemicals while performing the experiment.